Formalint

Browser-based developer tools

Timestamp Converter

Convert Unix timestamps, milliseconds and ISO dates into UTC and local browser time.

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Input

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Result

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Reference notes

Unix time without mental math

Seconds or milliseconds

Formalint detects common Unix seconds and Unix milliseconds values and shows both forms in the output.

UTC and local

UTC output is useful for logs and APIs, while local browser time helps compare what users actually see.

ISO input

Paste an ISO date string to convert it back into Unix timestamp values for tests, fixtures and API requests.