Weekday Occurrence Counter
Find out exactly how many times a chosen weekday occurs in any date range, plus a full breakdown of every weekday.
Weekday
Inclusive of both start and end dates
- 1
Total days in range
⌊(d2 − d1) ÷ 86,400,000⌋ + 1 = 365 - 2
Full weeks
⌊365 ÷ 7⌋ = 52 - 3
Remaining days
365 mod 7 = 1 - 4
Weekday offset from start day
(1 − 4 + 7) mod 7 = 4JS weekday numbers: 0 = Sunday … 6 = Saturday. Offset is how far the chosen weekday is past the start weekday within the partial-week tail. - 5
Occurrences
52 + 0 = 52
How does this calculator work?
This tool counts how many times any weekday occurs between two dates, inclusively. It adds up the total days, gives each weekday a base of total divided by seven, then distributes the leftover days starting from the start date's weekday. You get the chosen weekday's count plus a breakdown of all seven weekdays.
Formula
How this is calculated
Enter a start date and an end date (both inclusive) in YYYY-MM-DD form, then pick a single weekday or choose "All weekdays". The tool first computes the total number of days in the span as floor((end - start) / 86,400,000) + 1, counting both endpoints.
Every seven consecutive days contain exactly one of each weekday, so each weekday gets a base count of floor(total / 7). The leftover days, remainder = total mod 7, form a short run that begins on the start date's weekday and advances day by day. Each weekday falling inside that run receives one extra occurrence, which is why some weekdays can appear one more time than others.
Dates are parsed at UTC midnight to avoid daylight-saving and timezone shifts, so a whole-day difference is always exact. If the end date precedes the start date, or a date is malformed, no result is shown. The bar chart lists the count for all seven weekdays; the highlighted bar is your selected weekday.
Frequently asked questions
Yes. The range is inclusive, so a start and end on the same day counts as one day, and that day's weekday gets one occurrence.
Any range longer than a multiple of seven days has leftover days. Those extra days start on the start date's weekday, so the first few weekdays in that run get one additional count.
Use YYYY-MM-DD (for example 2026-12-31). Slashes and dots also work. Dates are interpreted at UTC midnight, so results are unaffected by timezones.
Also known as
TG we-Calculate Editorial Team. (2026). Weekday Occurrence Counter [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/weekday-occurrence-counter
TG we-Calculate Editorial Team. "Weekday Occurrence Counter." TG we-Calculate. 2026. https://we-calculate.com/calculator/weekday-occurrence-counter.
TG we-Calculate Editorial Team, "Weekday Occurrence Counter," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/weekday-occurrence-counter
@misc{wecalculate_weekday_occurrence_counter, title = {Weekday Occurrence Counter}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/weekday-occurrence-counter}}, year = {2026}, note = {TG we-Calculate} }
Did this calculator help you?