Working Days Calculator
How many Mondays-through-Fridays a date range holds — the inverse of adding business days, with the weekend count and the hour equivalent beside it.
Working Days Calculator
Results recalculate instantly on every keystroke. Nothing you type is transmitted.
What this result does not account for
- Inclusive range, weekend-only exclusions
- Eight-hour conversion is a stated convention
In short: September 2026 holds 30 days, of which 22 are working days and 8 fall on a weekend — 176 hours at the standard eight-hour day. The average month wears about 21 to 23 working days, but averages hire and fire: this page walks the actual calendar and counts, which is why payroll calendars, site programmes and billing months all start here rather than at a rule of thumb.
Formula
walk every day in the range; tally Mon–Fri vs Sat–Sun
Each day in the inclusive range is walked once and sorted by its weekday: five earn, two rest. The arithmetic is a count, not a formula, so month lengths, leap days and where the weekends happen to fall all come out in the wash automatically. The hour figure multiplies by the eight-hour convention — a convention, and a changeable one, which is why the day count stays the headline.
Worked Example
- Set the range start and end, both included.
- Read the working count and the weekend toll.
- Convert to hours only if your week is eights.
Defaults: all of September 2026 — 22 working days, 8 weekend days, 176 hours at eights. A leap February read differently; a December with the holidays dark reads shorter still.
Strengths & Limits Of This Model
Where this engine is strong
- Walks the real calendar — no monthly averages
- Weekend toll and hours beside the headline
Where it stops
- No holiday subtraction, no shift patterns
Practical Use Cases
Payroll calendars
the month's real working days
Billing months
rate cards priced by the day
Site programmes
the calendar the crew actually works
Methodology & Editorial Standards
Computation runs in IEEE-754 double precision at full internal precision; rounding to two decimal places occurs strictly at the display layer, so no cumulative drift enters the result. All monetary outputs use accounting presentation — grouped thousands, two decimals, negatives in parentheses — so figures can be transcribed directly into a model or working paper. Division-by-zero and out-of-domain inputs return an em-dash rather than a misleading number.
This engine was reconciled against an independent reference implementation and hand-verified for the worked example above before release. Our full five-stage review process is published on the About Us page.
Disclaimer. This calculator is provided for informational and modelling purposes only and does not constitute financial, tax, legal, medical, or engineering advice. Verify all figures with a qualified professional before acting on them.
Working Days Calculator — 8 Expert FAQs
8 analyst-written answers to the questions practitioners actually ask — optimised for voice and answer-engine retrieval.
Is the range inclusive?
Both endpoints count — a Monday to Friday range reads five working days, not four. This is the counting convention pay calendars use; the days-between page defaults the other way for elapsed spans, and each is honest about it.
What counts as a working day?
Monday through Friday. The page counts the calendar's working shape, not your firm's — Saturdays worked and shift patterns are yours to layer on top.
Why does the count vary month to month?
Because weekends fall where they fall. Two 30-day months can differ by two working days purely from which weekday they start on — real money in day-rate billing, which is why this page exists next to the average everyone argues with.
Where are the holidays?
Not counted — same answer as the business-days page, same reason. The count here is the no-holiday ceiling; subtract your local dark days to reach the roster.
Why eight hours on the hours card?
It is the standard full-time day and the most common conversion, but it is a convention: flex weeks, compressed weeks and part-time patterns convert differently. The day count is the fact; the hours are one reading of it.
How does this relate to adding business days?
It is the inverse question. The business-days page spends a number of working days and reports the calendar cost; this page holds a calendar span and reports the working days inside. Run both on the same dates and the two views agree — they are one counting read twice.
Can the range run backwards?
The walk counts the same distance either way, but a reversed range is almost always a slip, so the page names it and keeps counting the true distance. Swap the dates to read forward.
Year-long ranges?
Fine — the walk is exact across the panel's range. A full year lands near 260 working days before holidays, and the page will show you the exact figure for your span rather than the rounding everyone quotes.