This is today's date on the regular (Gregorian) calendar:
Thursday
8
May
2025
Friday
9
May
2025
Saturday
10
May
2025
Sunday
11
May
2025
Monday
12
May
2025
Today
Tuesday
13
May
2025
Wednesday
14
May
2025
Thursday
15
May
2025
Friday
16
May
2025
Saturday
17
May
2025
Sunday
18
May
2025
…and this is the same date on the World calendar:
Monday
6
May
2025
Tuesday
7
May
2025
Wednesday
8
May
2025
Thursday
9
May
2025
Friday
10
May
2025
Today
Saturday
11
May
2025
Sunday
12
May
2025
Monday
13
May
2025
Tuesday
14
May
2025
Wednesday
15
May
2025
Thursday
16
May
2025
…and on the International fixed calendar:
Monday
16
May
2025
Tuesday
17
May
2025
Wednesday
18
May
2025
Thursday
19
May
2025
Friday
20
May
2025
Today
Saturday
21
May
2025
Sunday
22
May
2025
Monday
23
May
2025
Tuesday
24
May
2025
Wednesday
25
May
2025
Thursday
26
May
2025
What about a decimal calendar?
Decimal calendars have been attempted, but none have gathered much interest. Some had 10 months of ~36 days, some kept the 12 months, but divided them into 3 weeks of 10 days where the 5 or 6 extra days (to match a solar year) happen after the last month.