Days between two dates
Pick a start and end date for the exact gap in total days, weeks, and business days (Monday–Friday), counted in your timezone. It is the gap between the dates, so the start day is day 0 (not counted).
Dates
Type a date or pick one
Type a date or pick one
Counted in UTCtoday not counted
Assumptions and sources
- Timezone
- UTC (UTC)
- Counting
- Today not counted
- Valid for
- 2026-09-04
- Result ID
- tw1-e7f1604a2cfc5e0e
4 weeksand 2 days 20 business days Holiday calendar: None
30 days between Friday, September 4, 2026 and Sunday, October 4, 2026, the gap, so the start date is not counted.
Calculation receipt
- Answer
- 30 days
- Operation
days_between- Inputs
- from: 2026-09-04 · to: 2026-10-04
- Timezone
- UTC
- Convention
- Whole calendar days, midnight to midnight; today = day 0 (not counted)
- Workweek
- mon-fri
- Holiday calendar
- None
- Valid for
- 2026-09-04 in UTC
- Computed at
- 2026-09-04T04:41:47.319Z
- Versions
- engine 1.0.0 · holiday dataset 2026.07.2
- Result ID
Same inputs, engine, and dataset always reproduce this ID; anyone can verify the answer from the fields above.
How the calculation works
tilwhen counts the whole calendar days between the two dates, the gap, not the span. That means the two endpoints are not both counted. If you need the duration that includes both the first and last day (for example, a hotel stay billed "Monday through Friday"), add one to the result. This is the difference between inclusive and exclusive counting, and it is the most common source of off-by-one errors.
What it's useful for
- Project and contract durations, how long a period actually runs.
- Anniversaries and milestones, days since a wedding, a birth, a job start date.
- Trip and event planning, the length of a stay or the gap before an event.
- Deadlines, how many days you have left until a fixed due date (see how to count a deadline).
Days, weeks, and business days
Alongside the total days, tilwhen shows the equivalent in weeks and days and the number of business days (Monday–Friday, weekends skipped), plus an optional figure that also excludes national public holidays for your country; see how to count business days correctly for the full method. All counting is done in your local timezone, read why that matters in date math across time zones.
How we calculate
- Counts whole calendar days, midnight to midnight, in your local timezone.
- Counting is exclusive: today is day 0 and is not counted.
- Business days are Monday–Friday by default (other working weeks are selectable where offered). The holiday-aware result skips public holidays only for the holiday calendar you choose in the calculator: United States, United Kingdom (England & Wales), United Kingdom (Scotland), United Kingdom (Northern Ireland), Ireland, France, Canada, Australia, and Uganda, or your own custom list. There is no default calendar; each result names the one used and lists the excluded days.
- No login and no server: every result is computed in your browser, so you can verify it yourself.
Method and holiday data maintained by Alan Mwine, who works in Linux systems operations, DevOps and security, where time zones, scheduling and exact date arithmetic are daily work.
Sources
Tools