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PUBLISHED 3:53 PM EST | Nov 20, 2018
By Christie Aschwanden and Ella Koeze
Originally developed at Slate and now updated with an improved prediction formula
Predicted marathon time
00:00:0000:00:00
Target split: 00:00:00
CORRECTION (Nov. 3, 3:20 p.m.): An earlier version of this calculator asked readers to submit the wrong training information. It requires a runner’s weekly mileage while training for a marathon, not for shorter races.
The formula powering this calculator was developed by Andrew Vickers and Emily Vertosick of the Memorial Sloan Kettering Cancer Center and is based on a survey of Slate readers conducted in 2014 (2,497 respondents). Read more »
Additional contributions from Reuben Fischer-Baum.
© 2025 ABC News Internet Ventures. All rights reserved.