BROWSER-ONLY DATE TOOL · Date, Time & Scheduling
Date Sequence Gap Finder
Find missing dates between observed dates when a fixed day interval is expected.
With 1 and 4 January 2025 and a one-day interval, 2 and 3 January are missing.
Set up your dates
Enter the values for this task. The example shows the expected input format.
Your result
Missing dates
UNDERSTAND THE RESULT
How to use the Date Sequence Gap Finder
Use this to audit a date-only log or export that should arrive at a regular day interval. The missing-date list points to places to investigate without changing the source data.
What to enter
Paste 2 to 100 dates in YYYY-MM-DD format, separated by lines or commas, and enter the expected day interval. The tool sorts the dates before comparing neighboring observations.
Worked example
With 1 and 4 January 2025 and a one-day interval, 2 and 3 January are missing.
How to read the result
Each row names a missing expected date and the observed dates on either side. Use those neighbors to find the relevant part of the original record or request a missing entry.
How the result is worked out
Sort unique supplied dates, then step by the entered interval between each pair and list expected dates that are absent.
What to check
The tool assumes a fixed calendar-day interval and lists at most 366 gaps. It does not infer business-day or irregular schedules.
A common mistake to avoid
This model assumes a fixed calendar-day cadence. It does not understand weekends, business days, irregular sampling, or skipped dates that were intentional.
This tool calculates in your browser. The dates you enter are not sent to the Nirmion API.
Questions to check
Can I paste dates out of order?
Yes. They are sorted before gaps are calculated; duplicate dates are rejected.
Why are duplicate dates rejected?
A duplicate is an ambiguous observation for a unique date sequence. Remove or investigate repeated dates before checking gaps.
Can I check a weekly sequence?
Yes. Set the expected interval to seven calendar days, provided the observations truly follow that fixed cadence.