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ISO week number calculator
ISO week number calculator — choose your inputs and copy or save the result. Input guide: Start date. No account needed.
No account needed
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How to use
- 1Input guide: Start date.
- 2Run the tool and review the result.
- 3Copy result / Save result file.
Good to know
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Worked input and output example
These results come from this tool’s actual engine using the sample values below, not your personal input or saved work. Load the example in the tool to inspect the same inputs.
Example input
| Field | Value |
|---|---|
| Start date | 2026-10-14 |
Example result
- Year
- 2,026
- Week number
- 42
2026-W42