Free tool / Dates
UK date
to ISO.
Convert one UK date per line into YYYY-MM-DD, with a time when you supply one.
Runs in your browser. Nothing you paste is stored or sent.
Day first. Two-digit years mean 20xx. Blank lines receive a line error. Maximum 200,000 characters.
Results
Your results will appear here.
How to use it
- Paste dates such as
05/10/2026,5/10/26,5 Oct 2026or05-10-2026 14:30. - Select Convert dates. Valid lines become
2026-10-05or2026-10-05T14:30. Full English month names also work. - Fix any line errors, then select and copy the results you need.
Times use a 24-hour clock. No timezone conversion is applied, and no timezone is inferred. Invalid calendar dates are rejected.
Zapier Formatter tips
In Zapier, choose Formatter > Date/Time > Format Date. Set input format to DD/MM/YYYY and output format to YYYY-MM-DD. Check timezone settings separately if your workflow includes times.
The US MM/DD/YYYY format can silently swap the month and day. Here, 05/10/2026 always means 5 October. Check a date with a day above 12 before turning on your Zap.
Need help repairing a date mapping or Python integration? See Python repair or all services.