Race blueprint
1:45:00 half marathon Blueprint
- Target time
- 1:45:00
- Target pace
- 4:59 /KM
Even-pace splits
- 5 KM24:53
- 10 KM49:46
- 15 KM1:14:39
- 20 KM1:39:32
- Finish1:45:00
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Featured: half marathon pace
Open the full tool →Change finish time, pace, speed, or any split; the rest stay even. The dedicated tool page has method and FAQs.
Your goal
8:01 /MI
Change finish time, pace, speed, or any split. The rest stay even.
Your splits
| Marker | Split | Time |
|---|---|---|
| 5 KM | 24:53 | |
| 10 KM | 24:53 | |
| 15 KM | 24:53 | |
| 20 KM | 24:53 | |
| Finish | 5:28 |
Your race blueprint
A 1:45 half marathon requires an average pace of approximately 4:59/km.
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Pace is finish time divided by distance. Displayed times round to the nearest second. Model-based tools use published formulas: Riegel, Daniels VDOT, Tanaka, Minetti, and interpolated WMA 2015 age-grading factors.
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Runners Lab is a free, no-login collection of running calculators. Search, calculate, get an answer, then open another tool. No accounts, no training diary, no AI in the math.