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    ISO 8601 Duration Converter

    Date & Time

    Parse ISO 8601 duration strings or build new ones from years, months, weeks, days, and time units.

    ISO 8601 → Breakdown

    Examples: P3Y6M4DT12H30M5S, P1W, PT45S, -P2DT3H.
    Breakdown --
    Normalized ISO --
    Approx. Total Seconds --
    Approx. Total Milliseconds --

    Breakdown → ISO 8601

    ISO 8601 --
    Readable Duration --
    Approx. Total Seconds --
    Approx. Total Milliseconds --

    How it works

    ISO format: Use P[nY][nM][nD][T[nH][nM][nS]] or P[nW], with an optional leading sign.
    Normalized output: Removes empty units and standardizes decimal formatting.
    Approximate totals: 1 year = 365 days, 1 month = 30 days.
    Private: All conversions run locally in your browser.

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