Add/subtract days, count between dates, working days, hours from now, and track work time. Works offline.
Users
2
store count
Rating
0.0 / 5
unchanged in 30 days
Ratings
0
total ratings
Store rank
#366K
#276K among extensions
Version
1.0.1
updated 1 Oct 2026
Users
monthly, 1 months
Latest, 15 Oct 2026:2 usersMove the mouse over the chart for any month
Ratings count
monthly, 1 months
Latest, 15 Oct 2026:0 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About CalculatorSpan Date & Time Tools
Four date and time calculators in one popup. No sign-up, no tracking, and it works offline.
WHAT YOU CAN DO
Add or subtract from a date
Pick a date, choose days, weeks, months or years, and get the exact result. Month ends are handled properly: add one month to January 31 and you get February 28, or February 29 in a leap year, and the extension tells you why.
Count days between two dates
Get the gap in years, months and days, plus total days, weeks, months and hours. Tick one box to include the end date.
Count working days
Business days between two dates, Monday to Friday by default. Change which days count as the weekend for a six or seven day week, and paste in your own holiday dates to exclude them.
Hours from now, or hours ago
Enter any number of hours and minutes and see the exact clock time and date it lands on, with the weekday and whether it crosses midnight.
DETAILS
Every result shows the weekday, day of the year and ISO week number where relevant. One click copies the result to your clipboard. Leap years and different month lengths are handled automatically.
The extension asks for no permissions at all. It cannot read your browsing history,