Today in two calendars
GregorianThursday ·September 242026
International Fixed CalendarSunday ·September 152026Month 10 of 13 · Week 3 of 4
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Today in two calendars
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wb_sunny
The structureA month called Solaris
It sits between June and July. Named after the sun. Everything else keeps its name — January is still January, December is still December. There's just one more month in between.
photo_camera
HistoryKodak used a fixed calendar for 61 years
From 1928 to 1989, Kodak used the system internally for accounting and planning while keeping Gregorian dates outside.
loop
Fixed civil weekdaysWhat about the uninterrupted seven-day cycle?
This is a genuine social choice, not a problem that mathematics can settle for everyone.
calendar_view_month
The structure13 equal months
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
light_mode
Astronomical layersThe solar year around the calendar
Equinoxes, solstices, perihelion and aphelion are calculated for the selected year. Sunrise and sunset are optional and require a location.
schedule
The Moon without mythsAn exact instant, shown in your time zone
A named phase is an astronomical instant. Its visible appearance changes gradually over several nights and its local date can differ by time zone.
event_available
What about the uninterrupted seven-day cycle?Fixed civil weekdays
Keep the special days outside the civil week. Monthly dates remain permanently aligned.
health_and_safety
The Moon without mythsAstronomy is not a health protocol
The project does not claim that lunar phases detoxify the body, control hormones, treat parasites or impose a universal menstrual cycle. Cultural traditions may be described only when clearly separated from scientific evidence.
wb_twilight
Astronomical layersSunrise and sunset
Coordinates are used only in this browser for the selected date and are never sent to our server.
nights_stay
AstronomyA 28-day month is not a lunar cycle
The average cycle from one New Moon to the next lasts 29.53 days, so phases drift through fixed months.
sync
What about the uninterrupted seven-day cycle?Continuous seven-day count
Give every elapsed day a weekday position. Religious and civil counting stay aligned, but monthly weekdays shift after a Special Day.
event_repeat
Interactive converterShared calculation engine
In regular IFC dates, the same month and day always return to the same civil weekday.
wb_sunny
The structureA month called Solaris
It sits between June and July. Named after the sun. Everything else keeps its name — January is still January, December is still December. There's just one more month in between.
photo_camera
HistoryKodak used a fixed calendar for 61 years
From 1928 to 1989, Kodak used the system internally for accounting and planning while keeping Gregorian dates outside.
loop
Fixed civil weekdaysWhat about the uninterrupted seven-day cycle?
This is a genuine social choice, not a problem that mathematics can settle for everyone.
calendar_view_month
The structure13 equal months
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
light_mode
Astronomical layersThe solar year around the calendar
Equinoxes, solstices, perihelion and aphelion are calculated for the selected year. Sunrise and sunset are optional and require a location.
schedule
The Moon without mythsAn exact instant, shown in your time zone
A named phase is an astronomical instant. Its visible appearance changes gradually over several nights and its local date can differ by time zone.
event_available
What about the uninterrupted seven-day cycle?Fixed civil weekdays
Keep the special days outside the civil week. Monthly dates remain permanently aligned.
health_and_safety
The Moon without mythsAstronomy is not a health protocol
The project does not claim that lunar phases detoxify the body, control hormones, treat parasites or impose a universal menstrual cycle. Cultural traditions may be described only when clearly separated from scientific evidence.
wb_twilight
Astronomical layersSunrise and sunset
Coordinates are used only in this browser for the selected date and are never sent to our server.
nights_stay
AstronomyA 28-day month is not a lunar cycle
The average cycle from one New Moon to the next lasts 29.53 days, so phases drift through fixed months.
sync
What about the uninterrupted seven-day cycle?Continuous seven-day count
Give every elapsed day a weekday position. Religious and civil counting stay aligned, but monthly weekdays shift after a Special Day.
event_repeat
Interactive converterShared calculation engine
In regular IFC dates, the same month and day always return to the same civil weekday.
wb_sunny
The structureA month called Solaris
It sits between June and July. Named after the sun. Everything else keeps its name — January is still January, December is still December. There's just one more month in between.
photo_camera
HistoryKodak used a fixed calendar for 61 years
From 1928 to 1989, Kodak used the system internally for accounting and planning while keeping Gregorian dates outside.
loop
Fixed civil weekdaysWhat about the uninterrupted seven-day cycle?
This is a genuine social choice, not a problem that mathematics can settle for everyone.
calendar_view_month
The structure13 equal months
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
light_mode
Astronomical layersThe solar year around the calendar
Equinoxes, solstices, perihelion and aphelion are calculated for the selected year. Sunrise and sunset are optional and require a location.
schedule
The Moon without mythsAn exact instant, shown in your time zone
A named phase is an astronomical instant. Its visible appearance changes gradually over several nights and its local date can differ by time zone.
event_available
What about the uninterrupted seven-day cycle?Fixed civil weekdays
Keep the special days outside the civil week. Monthly dates remain permanently aligned.
health_and_safety
The Moon without mythsAstronomy is not a health protocol
The project does not claim that lunar phases detoxify the body, control hormones, treat parasites or impose a universal menstrual cycle. Cultural traditions may be described only when clearly separated from scientific evidence.
wb_twilight
Astronomical layersSunrise and sunset
Coordinates are used only in this browser for the selected date and are never sent to our server.
nights_stay
AstronomyA 28-day month is not a lunar cycle
The average cycle from one New Moon to the next lasts 29.53 days, so phases drift through fixed months.
sync
What about the uninterrupted seven-day cycle?Continuous seven-day count
Give every elapsed day a weekday position. Religious and civil counting stay aligned, but monthly weekdays shift after a Special Day.
event_repeat
Interactive converterShared calculation engine
In regular IFC dates, the same month and day always return to the same civil weekday.
wb_sunny
The structureA month called Solaris
It sits between June and July. Named after the sun. Everything else keeps its name — January is still January, December is still December. There's just one more month in between.
photo_camera
HistoryKodak used a fixed calendar for 61 years
From 1928 to 1989, Kodak used the system internally for accounting and planning while keeping Gregorian dates outside.
loop
Fixed civil weekdaysWhat about the uninterrupted seven-day cycle?
This is a genuine social choice, not a problem that mathematics can settle for everyone.
calendar_view_month
The structure13 equal months
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
light_mode
Astronomical layersThe solar year around the calendar
Equinoxes, solstices, perihelion and aphelion are calculated for the selected year. Sunrise and sunset are optional and require a location.
schedule
The Moon without mythsAn exact instant, shown in your time zone
A named phase is an astronomical instant. Its visible appearance changes gradually over several nights and its local date can differ by time zone.
event_available
What about the uninterrupted seven-day cycle?Fixed civil weekdays
Keep the special days outside the civil week. Monthly dates remain permanently aligned.
health_and_safety
The Moon without mythsAstronomy is not a health protocol
The project does not claim that lunar phases detoxify the body, control hormones, treat parasites or impose a universal menstrual cycle. Cultural traditions may be described only when clearly separated from scientific evidence.
wb_twilight
Astronomical layersSunrise and sunset
Coordinates are used only in this browser for the selected date and are never sent to our server.
nights_stay
AstronomyA 28-day month is not a lunar cycle
The average cycle from one New Moon to the next lasts 29.53 days, so phases drift through fixed months.
sync
What about the uninterrupted seven-day cycle?Continuous seven-day count
Give every elapsed day a weekday position. Religious and civil counting stay aligned, but monthly weekdays shift after a Special Day.
event_repeat
Interactive converterShared calculation engine
In regular IFC dates, the same month and day always return to the same civil weekday.
wb_sunny
The structureA month called Solaris
It sits between June and July. Named after the sun. Everything else keeps its name — January is still January, December is still December. There's just one more month in between.
photo_camera
HistoryKodak used a fixed calendar for 61 years
From 1928 to 1989, Kodak used the system internally for accounting and planning while keeping Gregorian dates outside.
loop
Fixed civil weekdaysWhat about the uninterrupted seven-day cycle?
This is a genuine social choice, not a problem that mathematics can settle for everyone.
calendar_view_month
The structure13 equal months
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
light_mode
Astronomical layersThe solar year around the calendar
Equinoxes, solstices, perihelion and aphelion are calculated for the selected year. Sunrise and sunset are optional and require a location.
schedule
The Moon without mythsAn exact instant, shown in your time zone
A named phase is an astronomical instant. Its visible appearance changes gradually over several nights and its local date can differ by time zone.
event_available
What about the uninterrupted seven-day cycle?Fixed civil weekdays
Keep the special days outside the civil week. Monthly dates remain permanently aligned.
health_and_safety
The Moon without mythsAstronomy is not a health protocol
The project does not claim that lunar phases detoxify the body, control hormones, treat parasites or impose a universal menstrual cycle. Cultural traditions may be described only when clearly separated from scientific evidence.
wb_twilight
Astronomical layersSunrise and sunset
Coordinates are used only in this browser for the selected date and are never sent to our server.
nights_stay
AstronomyA 28-day month is not a lunar cycle
The average cycle from one New Moon to the next lasts 29.53 days, so phases drift through fixed months.
sync
What about the uninterrupted seven-day cycle?Continuous seven-day count
Give every elapsed day a weekday position. Religious and civil counting stay aligned, but monthly weekdays shift after a Special Day.
event_repeat
Interactive converterShared calculation engine
In regular IFC dates, the same month and day always return to the same civil weekday.
wb_sunny
The structureA month called Solaris
It sits between June and July. Named after the sun. Everything else keeps its name — January is still January, December is still December. There's just one more month in between.
photo_camera
HistoryKodak used a fixed calendar for 61 years
From 1928 to 1989, Kodak used the system internally for accounting and planning while keeping Gregorian dates outside.
loop
Fixed civil weekdaysWhat about the uninterrupted seven-day cycle?
This is a genuine social choice, not a problem that mathematics can settle for everyone.
calendar_view_month
The structure13 equal months
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
light_mode
Astronomical layersThe solar year around the calendar
Equinoxes, solstices, perihelion and aphelion are calculated for the selected year. Sunrise and sunset are optional and require a location.
schedule
The Moon without mythsAn exact instant, shown in your time zone
A named phase is an astronomical instant. Its visible appearance changes gradually over several nights and its local date can differ by time zone.
event_available
What about the uninterrupted seven-day cycle?Fixed civil weekdays
Keep the special days outside the civil week. Monthly dates remain permanently aligned.
health_and_safety
The Moon without mythsAstronomy is not a health protocol
The project does not claim that lunar phases detoxify the body, control hormones, treat parasites or impose a universal menstrual cycle. Cultural traditions may be described only when clearly separated from scientific evidence.
wb_twilight
Astronomical layersSunrise and sunset
Coordinates are used only in this browser for the selected date and are never sent to our server.
nights_stay
AstronomyA 28-day month is not a lunar cycle
The average cycle from one New Moon to the next lasts 29.53 days, so phases drift through fixed months.
sync
What about the uninterrupted seven-day cycle?Continuous seven-day count
Give every elapsed day a weekday position. Religious and civil counting stay aligned, but monthly weekdays shift after a Special Day.
event_repeat
Interactive converterShared calculation engine
In regular IFC dates, the same month and day always return to the same civil weekday.
wb_sunny
The structureA month called Solaris
It sits between June and July. Named after the sun. Everything else keeps its name — January is still January, December is still December. There's just one more month in between.
photo_camera
HistoryKodak used a fixed calendar for 61 years
From 1928 to 1989, Kodak used the system internally for accounting and planning while keeping Gregorian dates outside.
loop
Fixed civil weekdaysWhat about the uninterrupted seven-day cycle?
This is a genuine social choice, not a problem that mathematics can settle for everyone.
calendar_view_month
The structure13 equal months
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
light_mode
Astronomical layersThe solar year around the calendar
Equinoxes, solstices, perihelion and aphelion are calculated for the selected year. Sunrise and sunset are optional and require a location.
schedule
The Moon without mythsAn exact instant, shown in your time zone
A named phase is an astronomical instant. Its visible appearance changes gradually over several nights and its local date can differ by time zone.
event_available
What about the uninterrupted seven-day cycle?Fixed civil weekdays
Keep the special days outside the civil week. Monthly dates remain permanently aligned.
health_and_safety
The Moon without mythsAstronomy is not a health protocol
The project does not claim that lunar phases detoxify the body, control hormones, treat parasites or impose a universal menstrual cycle. Cultural traditions may be described only when clearly separated from scientific evidence.
wb_twilight
Astronomical layersSunrise and sunset
Coordinates are used only in this browser for the selected date and are never sent to our server.
nights_stay
AstronomyA 28-day month is not a lunar cycle
The average cycle from one New Moon to the next lasts 29.53 days, so phases drift through fixed months.
sync
What about the uninterrupted seven-day cycle?Continuous seven-day count
Give every elapsed day a weekday position. Religious and civil counting stay aligned, but monthly weekdays shift after a Special Day.
event_repeat
Interactive converterShared calculation engine
In regular IFC dates, the same month and day always return to the same civil weekday.
Annual planner
Compare the complete year
Each IFC month is mapped to its Gregorian start and end. Export the month starts or print this planner as a PDF.
| IFC month | Gregorian range | Fixed weekday |
|---|---|---|
| 1 January | Jan 1 – Jan 28 | Sunday |
| 2 February | Jan 29 – Feb 25 | Sunday |
| 3 March | Feb 26 – Mar 25 | Sunday |
| 4 April | Mar 26 – Apr 22 | Sunday |
| 5 May | Apr 23 – May 20 | Sunday |
| 6 June | May 21 – Jun 17 | Sunday |
| 7 Solaris | Jun 18 – Jul 15 | Sunday |
| 8 July | Jul 16 – Aug 12 | Sunday |
| 9 August | Aug 13 – Sep 9 | Sunday |
| 10 September | Sep 10 – Oct 7 | Sunday |
| 11 October | Oct 8 – Nov 4 | Sunday |
| 12 November | Nov 5 – Dec 2 | Sunday |
| 13 December | Dec 3 – Dec 30 | Sunday |
Special Days
Year Day
13
13 Calendar
International Fixed Calendar
2026Thirteen equal months of 28 days make 364 regular days. Year Day, and Leap Day when needed, sit outside the months and the civil week.
13 Calendar
Compare the complete year
Because 28 divides perfectly into 4 weeks. No other month length does that. 13 × 28 = 364, which is as close to 365 as you can get with perfectly equal months.
13 equal months
17IFC dateAug 29Gregorian date
# 0
Compare the complete year
Thirteen equal months of 28 days make 364 regular days. Year Day, and Leap Day when needed, sit outside the months and the civil week.
JanuaryJan 1 – Jan 28
FebruaryJan 29 – Feb 25
MarchFeb 26 – Mar 25
AprilMar 26 – Apr 22
MayApr 23 – May 20
JuneMay 21 – Jun 17
SolarisJun 18 – Jul 15
JulyJul 16 – Aug 12
AugustAug 13 – Sep 9
SeptemberSep 10 – Oct 7
OctoberOct 8 – Nov 4
NovemberNov 5 – Dec 2
DecemberDec 3 – Dec 30
Special DaysDec 31 · —
# 1
01January
Jan 1 – Jan 28
SunMonTueWedThuFriSat
1Jan 1
2Jan 2
3Jan 3
4Jan 4
5Jan 5
6Jan 6
7Jan 7
8Jan 8
9Jan 9
10Jan 10
11Jan 11
12Jan 12
13Jan 13
14Jan 14
15Jan 15
16Jan 16
17Jan 17
18Jan 18
19Jan 19
20Jan 20
21Jan 21
22Jan 22
23Jan 23
24Jan 24
25Jan 25
26Jan 26
27Jan 27
28Jan 28
Monthly priorities
Notes
Notes
01January
1Jan 1
2Jan 2
3Jan 3
4Jan 4
5Jan 5
6Jan 6
7Jan 7
8Jan 8
9Jan 9
10Jan 10
11Jan 11
12Jan 12
13Jan 13
14Jan 14
15Jan 15
16Jan 16
17Jan 17
18Jan 18
19Jan 19
20Jan 20
21Jan 21
22Jan 22
23Jan 23
24Jan 24
25Jan 25
26Jan 26
27Jan 27
28Jan 28
# 2
02February
Jan 29 – Feb 25
SunMonTueWedThuFriSat
1Jan 29
2Jan 30
3Jan 31
4Feb 1
5Feb 2
6Feb 3
7Feb 4
8Feb 5
9Feb 6
10Feb 7
11Feb 8
12Feb 9
13Feb 10
14Feb 11
15Feb 12
16Feb 13
17Feb 14
18Feb 15
19Feb 16
20Feb 17
21Feb 18
22Feb 19
23Feb 20
24Feb 21
25Feb 22
26Feb 23
27Feb 24
28Feb 25
Monthly priorities
Notes
Notes
02February
1Jan 29
2Jan 30
3Jan 31
4Feb 1
5Feb 2
6Feb 3
7Feb 4
8Feb 5
9Feb 6
10Feb 7
11Feb 8
12Feb 9
13Feb 10
14Feb 11
15Feb 12
16Feb 13
17Feb 14
18Feb 15
19Feb 16
20Feb 17
21Feb 18
22Feb 19
23Feb 20
24Feb 21
25Feb 22
26Feb 23
27Feb 24
28Feb 25
# 3
03March
Feb 26 – Mar 25
SunMonTueWedThuFriSat
1Feb 26
2Feb 27
3Feb 28
4Mar 1
5Mar 2
6Mar 3
7Mar 4
8Mar 5
9Mar 6
10Mar 7
11Mar 8
12Mar 9
13Mar 10
14Mar 11
15Mar 12
16Mar 13
17Mar 14
18Mar 15
19Mar 16
20Mar 17
21Mar 18
22Mar 19
23Mar 20
24Mar 21
25Mar 22
26Mar 23
27Mar 24
28Mar 25
Monthly priorities
Notes
Notes
03March
1Feb 26
2Feb 27
3Feb 28
4Mar 1
5Mar 2
6Mar 3
7Mar 4
8Mar 5
9Mar 6
10Mar 7
11Mar 8
12Mar 9
13Mar 10
14Mar 11
15Mar 12
16Mar 13
17Mar 14
18Mar 15
19Mar 16
20Mar 17
21Mar 18
22Mar 19
23Mar 20
24Mar 21
25Mar 22
26Mar 23
27Mar 24
28Mar 25
# 4
04April
Mar 26 – Apr 22
SunMonTueWedThuFriSat
1Mar 26
2Mar 27
3Mar 28
4Mar 29
5Mar 30
6Mar 31
7Apr 1
8Apr 2
9Apr 3
10Apr 4
11Apr 5
12Apr 6
13Apr 7
14Apr 8
15Apr 9
16Apr 10
17Apr 11
18Apr 12
19Apr 13
20Apr 14
21Apr 15
22Apr 16
23Apr 17
24Apr 18
25Apr 19
26Apr 20
27Apr 21
28Apr 22
Monthly priorities
Notes
Notes
04April
1Mar 26
2Mar 27
3Mar 28
4Mar 29
5Mar 30
6Mar 31
7Apr 1
8Apr 2
9Apr 3
10Apr 4
11Apr 5
12Apr 6
13Apr 7
14Apr 8
15Apr 9
16Apr 10
17Apr 11
18Apr 12
19Apr 13
20Apr 14
21Apr 15
22Apr 16
23Apr 17
24Apr 18
25Apr 19
26Apr 20
27Apr 21
28Apr 22
# 5
05May
Apr 23 – May 20
SunMonTueWedThuFriSat
1Apr 23
2Apr 24
3Apr 25
4Apr 26
5Apr 27
6Apr 28
7Apr 29
8Apr 30
9May 1
10May 2
11May 3
12May 4
13May 5
14May 6
15May 7
16May 8
17May 9
18May 10
19May 11
20May 12
21May 13
22May 14
23May 15
24May 16
25May 17
26May 18
27May 19
28May 20
Monthly priorities
Notes
Notes
05May
1Apr 23
2Apr 24
3Apr 25
4Apr 26
5Apr 27
6Apr 28
7Apr 29
8Apr 30
9May 1
10May 2
11May 3
12May 4
13May 5
14May 6
15May 7
16May 8
17May 9
18May 10
19May 11
20May 12
21May 13
22May 14
23May 15
24May 16
25May 17
26May 18
27May 19
28May 20
# 6
06June
May 21 – Jun 17
SunMonTueWedThuFriSat
1May 21
2May 22
3May 23
4May 24
5May 25
6May 26
7May 27
8May 28
9May 29
10May 30
11May 31
12Jun 1
13Jun 2
14Jun 3
15Jun 4
16Jun 5
17Jun 6
18Jun 7
19Jun 8
20Jun 9
21Jun 10
22Jun 11
23Jun 12
24Jun 13
25Jun 14
26Jun 15
27Jun 16
28Jun 17
Monthly priorities
Notes
Notes
06June
1May 21
2May 22
3May 23
4May 24
5May 25
6May 26
7May 27
8May 28
9May 29
10May 30
11May 31
12Jun 1
13Jun 2
14Jun 3
15Jun 4
16Jun 5
17Jun 6
18Jun 7
19Jun 8
20Jun 9
21Jun 10
22Jun 11
23Jun 12
24Jun 13
25Jun 14
26Jun 15
27Jun 16
28Jun 17
# 7
07Solaris
Jun 18 – Jul 15
SunMonTueWedThuFriSat
1Jun 18
2Jun 19
3Jun 20
4Jun 21
5Jun 22
6Jun 23
7Jun 24
8Jun 25
9Jun 26
10Jun 27
11Jun 28
12Jun 29
13Jun 30
14Jul 1
15Jul 2
16Jul 3
17Jul 4
18Jul 5
19Jul 6
20Jul 7
21Jul 8
22Jul 9
23Jul 10
24Jul 11
25Jul 12
26Jul 13
27Jul 14
28Jul 15
Monthly priorities
Notes
Notes
07Solaris
1Jun 18
2Jun 19
3Jun 20
4Jun 21
5Jun 22
6Jun 23
7Jun 24
8Jun 25
9Jun 26
10Jun 27
11Jun 28
12Jun 29
13Jun 30
14Jul 1
15Jul 2
16Jul 3
17Jul 4
18Jul 5
19Jul 6
20Jul 7
21Jul 8
22Jul 9
23Jul 10
24Jul 11
25Jul 12
26Jul 13
27Jul 14
28Jul 15
# 8
08July
Jul 16 – Aug 12
SunMonTueWedThuFriSat
1Jul 16
2Jul 17
3Jul 18
4Jul 19
5Jul 20
6Jul 21
7Jul 22
8Jul 23
9Jul 24
10Jul 25
11Jul 26
12Jul 27
13Jul 28
14Jul 29
15Jul 30
16Jul 31
17Aug 1
18Aug 2
19Aug 3
20Aug 4
21Aug 5
22Aug 6
23Aug 7
24Aug 8
25Aug 9
26Aug 10
27Aug 11
28Aug 12
Monthly priorities
Notes
Notes
08July
1Jul 16
2Jul 17
3Jul 18
4Jul 19
5Jul 20
6Jul 21
7Jul 22
8Jul 23
9Jul 24
10Jul 25
11Jul 26
12Jul 27
13Jul 28
14Jul 29
15Jul 30
16Jul 31
17Aug 1
18Aug 2
19Aug 3
20Aug 4
21Aug 5
22Aug 6
23Aug 7
24Aug 8
25Aug 9
26Aug 10
27Aug 11
28Aug 12
# 9
09August
Aug 13 – Sep 9
SunMonTueWedThuFriSat
1Aug 13
2Aug 14
3Aug 15
4Aug 16
5Aug 17
6Aug 18
7Aug 19
8Aug 20
9Aug 21
10Aug 22
11Aug 23
12Aug 24
13Aug 25
14Aug 26
15Aug 27
16Aug 28
17Aug 29
18Aug 30
19Aug 31
20Sep 1
21Sep 2
22Sep 3
23Sep 4
24Sep 5
25Sep 6
26Sep 7
27Sep 8
28Sep 9
Monthly priorities
Notes
Notes
09August
1Aug 13
2Aug 14
3Aug 15
4Aug 16
5Aug 17
6Aug 18
7Aug 19
8Aug 20
9Aug 21
10Aug 22
11Aug 23
12Aug 24
13Aug 25
14Aug 26
15Aug 27
16Aug 28
17Aug 29
18Aug 30
19Aug 31
20Sep 1
21Sep 2
22Sep 3
23Sep 4
24Sep 5
25Sep 6
26Sep 7
27Sep 8
28Sep 9
# 10
10September
Sep 10 – Oct 7
SunMonTueWedThuFriSat
1Sep 10
2Sep 11
3Sep 12
4Sep 13
5Sep 14
6Sep 15
7Sep 16
8Sep 17
9Sep 18
10Sep 19
11Sep 20
12Sep 21
13Sep 22
14Sep 23
15Sep 24
16Sep 25
17Sep 26
18Sep 27
19Sep 28
20Sep 29
21Sep 30
22Oct 1
23Oct 2
24Oct 3
25Oct 4
26Oct 5
27Oct 6
28Oct 7
Monthly priorities
Notes
Notes
10September
1Sep 10
2Sep 11
3Sep 12
4Sep 13
5Sep 14
6Sep 15
7Sep 16
8Sep 17
9Sep 18
10Sep 19
11Sep 20
12Sep 21
13Sep 22
14Sep 23
15Sep 24
16Sep 25
17Sep 26
18Sep 27
19Sep 28
20Sep 29
21Sep 30
22Oct 1
23Oct 2
24Oct 3
25Oct 4
26Oct 5
27Oct 6
28Oct 7
# 11
11October
Oct 8 – Nov 4
SunMonTueWedThuFriSat
1Oct 8
2Oct 9
3Oct 10
4Oct 11
5Oct 12
6Oct 13
7Oct 14
8Oct 15
9Oct 16
10Oct 17
11Oct 18
12Oct 19
13Oct 20
14Oct 21
15Oct 22
16Oct 23
17Oct 24
18Oct 25
19Oct 26
20Oct 27
21Oct 28
22Oct 29
23Oct 30
24Oct 31
25Nov 1
26Nov 2
27Nov 3
28Nov 4
Monthly priorities
Notes
Notes
11October
1Oct 8
2Oct 9
3Oct 10
4Oct 11
5Oct 12
6Oct 13
7Oct 14
8Oct 15
9Oct 16
10Oct 17
11Oct 18
12Oct 19
13Oct 20
14Oct 21
15Oct 22
16Oct 23
17Oct 24
18Oct 25
19Oct 26
20Oct 27
21Oct 28
22Oct 29
23Oct 30
24Oct 31
25Nov 1
26Nov 2
27Nov 3
28Nov 4
# 12
12November
Nov 5 – Dec 2
SunMonTueWedThuFriSat
1Nov 5
2Nov 6
3Nov 7
4Nov 8
5Nov 9
6Nov 10
7Nov 11
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10Nov 14
11Nov 15
12Nov 16
13Nov 17
14Nov 18
15Nov 19
16Nov 20
17Nov 21
18Nov 22
19Nov 23
20Nov 24
21Nov 25
22Nov 26
23Nov 27
24Nov 28
25Nov 29
26Nov 30
27Dec 1
28Dec 2
Monthly priorities
Notes
Notes
12November
1Nov 5
2Nov 6
3Nov 7
4Nov 8
5Nov 9
6Nov 10
7Nov 11
8Nov 12
9Nov 13
10Nov 14
11Nov 15
12Nov 16
13Nov 17
14Nov 18
15Nov 19
16Nov 20
17Nov 21
18Nov 22
19Nov 23
20Nov 24
21Nov 25
22Nov 26
23Nov 27
24Nov 28
25Nov 29
26Nov 30
27Dec 1
28Dec 2
# 13
13December
Dec 3 – Dec 30
SunMonTueWedThuFriSat
1Dec 3
2Dec 4
3Dec 5
4Dec 6
5Dec 7
6Dec 8
7Dec 9
8Dec 10
9Dec 11
10Dec 12
11Dec 13
12Dec 14
13Dec 15
14Dec 16
15Dec 17
16Dec 18
17Dec 19
18Dec 20
19Dec 21
20Dec 22
21Dec 23
22Dec 24
23Dec 25
24Dec 26
25Dec 27
26Dec 28
27Dec 29
28Dec 30
Monthly priorities
Notes
Notes
13December
1Dec 3
2Dec 4
3Dec 5
4Dec 6
5Dec 7
6Dec 8
7Dec 9
8Dec 10
9Dec 11
10Dec 12
11Dec 13
12Dec 14
13Dec 15
14Dec 16
15Dec 17
16Dec 18
17Dec 19
18Dec 20
19Dec 21
20Dec 22
21Dec 23
22Dec 24
23Dec 25
24Dec 26
25Dec 27
26Dec 28
27Dec 29
28Dec 30
# 14
Year Day
Thirteen equal months of 28 days make 364 regular days. Year Day, and Leap Day when needed, sit outside the months and the civil week.
Year Day
Thursday, December 31, 2026
Notes
# 15
Leap Day
Thirteen equal months of 28 days make 364 regular days. Year Day, and Leap Day when needed, sit outside the months and the civil week.
Leap Day
This year has no Leap Day.
Notes
Notes · # 1
January
Notes · # 2
February
Notes · # 3
March
Notes · # 4
April
Notes · # 5
May
Notes · # 6
June
Notes · # 7
Solaris
Notes · # 8
July
Notes · # 9
August
Notes · # 10
September
Notes · # 11
October
Notes · # 12
November
Notes · # 13
December
13 Calendar · 2026
Special Days
13 Calendar
Sources before certainty
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13
13calendar.pages.devInternational Fixed Calendar · 202613
Thirteen equal months of 28 days make 364 regular days. Year Day, and Leap Day when needed, sit outside the months and the civil week.
13calendar.pages.devAstronomical layers
The solar year around the calendar
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Tuesday · January 3 · 2026
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Monday · March 23 · 2026
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June solstice
Wednesday · Solaris 4 · 2026
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Aphelion
Thursday · Solaris 19 · 2026
152.09 million km
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September equinox
Saturday · September 14 · 2026
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December solstice
Thursday · December 19 · 2026
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