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    Ironman Cutoff Calculator

    Will you beat the cutoffs? Enter your projected swim, bike, and run splits and this calculator checks them against the official Ironman and 70.3 segment cutoffs and the overall time limit.

    Your projected splits

    Enter realistic race-day paces — including transitions — to see your margins.

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    Last updated: June 2026Reviewed by: Bryan Collins, founder

    How this calculator works

    Segment times are derived from your entered swim pace per 100m, bike average speed, and run pace, plus your transition estimates. Cumulative elapsed times are compared against IRONMAN's published segment cutoffs and overall time limit.

    Assumptions

    • • Swim cutoff includes T1; bike cutoff is measured off the bike (after T2)
    • • Even pacing across each leg
    • • Standard IRONMAN cutoffs as published at ironman.com

    Limitations

    • • Some races set their own intermediate cutoffs and start waves
    • • Conditions (heat, current, hills) can change real splits significantly

    Who this is for

    • • First-time Ironman and 70.3 athletes pacing for the cutoffs
    • • Back-of-pack athletes planning realistic splits
    • • Anyone choosing transition and bike targets to stay safe

    Who this is not for

    • • Drafting-legal or non-IRONMAN-branded events with different rules
    • • Predicting an exact finish time (use the Race Time Calculator)

    References

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    Ironman Cutoff Calculator FAQ

    Scientific References

    IRONMAN Official Competition Rules and Athlete Guide. ironman.com.

    Official IRONMAN competition rules including cutoff times for all race distances