WhatWeek

2025 Calendar with Week Numbers

View ISO week numbers, US-style comparison, week date ranges, and month calendars for 2025.

ISO weeks in 2025

52

12-month calendar view

Scan the year by quarter, month, and ISO week before opening the full data table below.

Year atlas

2025 mapped across 52 ISO weeks

Scan the year by week, quarter, and month. The ribbon marks the current ISO week and makes the full ISO year visible before you dive into each month.

ISO year length

52

Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Week 16 Week 17 Week 18 Week 19 Week 20 Week 21 Week 22 Week 23 Week 24 Week 25 Week 26 Week 27 Week 28 Week 29 Week 30 Week 31 Week 32 Week 33 Week 34 Week 35 Week 36 Week 37 Week 38 Week 39 Week 40 Week 41 Week 42 Week 43 Week 44 Week 45 Week 46 Week 47 Week 48 Week 49 Week 50 Week 51 Week 52
W1 Quarter start
W1 quarter start Current week

Q1

W1-W14

Jan · Feb · Mar

Q2

W14-W27

Apr · May · Jun

Q3

W27-W40

Jul · Aug · Sep

Q4

W40-W52

Oct · Nov · Dec

Quarter 1

Q1 planning view

W1-W14

Q1

January

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
1
2
3
4
5
6

Q1

February

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
5
6
7
8
9
10

Q1

March

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
9
10
11
12
13
14

Quarter 2

Q2 planning view

W14-W27

Q2

April

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
14
15
16
17
18
19

Q2

May

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
18
19
20
21
22
23

Q2

June

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
22
23
24
25
26
27

Quarter 3

Q3 planning view

W27-W40

Q3

July

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
27
28
29
30
31
32

Q3

August

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
31
32
33
34
35
36

Q3

September

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
36
37
38
39
40
41

Quarter 4

Q4 planning view

W40-W52

Q4

October

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
40
41
42
43
44
45

Q4

November

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
44
45
46
47
48
49

Q4

December

Wk
Mon
Tue
Wed
Thu
Fri
Sat
Sun
49
50
51
52
1
2

ISO vs US-style week comparison

ISO weeks start on Monday and Week 1 contains January 4. The simplified US-style week shown here starts on Sunday and Week 1 contains January 1, so the week number and date range can differ.

Date ISO week ISO range US-style week US-style range
2025-01-01 2025-W01 2024-12-30 to 2025-01-05 Week 1 2024-12-29 to 2025-01-04
2025-05-03 2025-W18 2025-04-28 to 2025-05-04 Week 18 2025-04-27 to 2025-05-03
2025-12-31 2026-W01 2025-12-29 to 2026-01-04 Week 53 2025-12-28 to 2026-01-03

ISO week table

Download CSV Next year

CSV columns: year, week, system, weekStarts, weekEnds, plus legacy weekday/weekend count fields. Open the CSV in Excel or Google Sheets to sort by week number, filter planning periods, or combine WhatWeek date ranges with your own spreadsheet data.

Week ISO notation Starts Ends Weekdays
Week 1 W01 2024-12-30 2025-01-05 5
Week 2 W02 2025-01-06 2025-01-12 5
Week 3 W03 2025-01-13 2025-01-19 5
Week 4 W04 2025-01-20 2025-01-26 5
Week 5 W05 2025-01-27 2025-02-02 5
Week 6 W06 2025-02-03 2025-02-09 5
Week 7 W07 2025-02-10 2025-02-16 5
Week 8 W08 2025-02-17 2025-02-23 5
Week 9 W09 2025-02-24 2025-03-02 5
Week 10 W10 2025-03-03 2025-03-09 5
Week 11 W11 2025-03-10 2025-03-16 5
Week 12 W12 2025-03-17 2025-03-23 5
Week 13 W13 2025-03-24 2025-03-30 5
Week 14 W14 2025-03-31 2025-04-06 5
Week 15 W15 2025-04-07 2025-04-13 5
Week 16 W16 2025-04-14 2025-04-20 5
Week 17 W17 2025-04-21 2025-04-27 5
Week 18 W18 2025-04-28 2025-05-04 5
Week 19 W19 2025-05-05 2025-05-11 5
Week 20 W20 2025-05-12 2025-05-18 5
Week 21 W21 2025-05-19 2025-05-25 5
Week 22 W22 2025-05-26 2025-06-01 5
Week 23 W23 2025-06-02 2025-06-08 5
Week 24 W24 2025-06-09 2025-06-15 5
Week 25 W25 2025-06-16 2025-06-22 5
Week 26 W26 2025-06-23 2025-06-29 5
Week 27 W27 2025-06-30 2025-07-06 5
Week 28 W28 2025-07-07 2025-07-13 5
Week 29 W29 2025-07-14 2025-07-20 5
Week 30 W30 2025-07-21 2025-07-27 5
Week 31 W31 2025-07-28 2025-08-03 5
Week 32 W32 2025-08-04 2025-08-10 5
Week 33 W33 2025-08-11 2025-08-17 5
Week 34 W34 2025-08-18 2025-08-24 5
Week 35 W35 2025-08-25 2025-08-31 5
Week 36 W36 2025-09-01 2025-09-07 5
Week 37 W37 2025-09-08 2025-09-14 5
Week 38 W38 2025-09-15 2025-09-21 5
Week 39 W39 2025-09-22 2025-09-28 5
Week 40 W40 2025-09-29 2025-10-05 5
Week 41 W41 2025-10-06 2025-10-12 5
Week 42 W42 2025-10-13 2025-10-19 5
Week 43 W43 2025-10-20 2025-10-26 5
Week 44 W44 2025-10-27 2025-11-02 5
Week 45 W45 2025-11-03 2025-11-09 5
Week 46 W46 2025-11-10 2025-11-16 5
Week 47 W47 2025-11-17 2025-11-23 5
Week 48 W48 2025-11-24 2025-11-30 5
Week 49 W49 2025-12-01 2025-12-07 5
Week 50 W50 2025-12-08 2025-12-14 5
Week 51 W51 2025-12-15 2025-12-21 5
Week 52 W52 2025-12-22 2025-12-28 5