50K Pace Chart

What a 50K pace chart shows

A 50K pace chart turns an ultra finish time over 50 kilometres, or 31.0686 miles, into the average pace for the whole course. It is plain arithmetic, the time divided by 50, so the average includes every aid station stop and every walked climb along the way.

Reading a 50K chart differently from a road chart

On a road marathon, average pace and running pace are close to the same thing. On a 50K they often are not. If you plan 4 stops of 2 minutes inside a 6:00:00 finish, those 8 minutes come out of the running: the chart row says 7:12 per km, but the pace you have to hold while moving is 7:02 per km.

The practical way to use this page is often in reverse. Decide what average pace is realistic for the terrain, find it in the pace column, and read the finish time it produces. That is a more honest planning direction than picking a finish time first, particularly on a course with real climbing.

Checkpoints, rows and the finder

The table covers 2:30:00 to 13:00:00 in rows every 5 minutes, grouped by the hour, so the long finishes of a hilly trail race are on the chart as well as fast road ultras. The 10K, half marathon and marathon columns show where an even-paced runner would be: a 6:00:00 50K passes 10K at 1:12:00, the half marathon mark at 2:31:54 and the marathon at 5:03:48. If you expect to slow late in the race, you need to reach each checkpoint earlier than these columns show. For a time between rows, such as 12:30:00 or 5h47m, the finder gives the exact pace and all three splits. Copy table, Download CSV and Print cover the whole chart, and the PNG below fits on one A4 sheet for a drop bag.

Why prediction breaks down past the marathon

The race time predictorand the equivalent times tables elsewhere on this site use Riegel's formula, t2 = t1 x (d2 / d1) ^ 1.06. That model was fitted to endurance race performances and it works reasonably from 5K up to the marathon. At 50 km and beyond it starts to mislead, for reasons that have nothing to do with the exponent: ultras are frequently run on trail rather than road, they involve deliberate walking, they involve eating, and the variation between individuals in how well they hold pace past four hours is far larger than at marathon distance.

PaceLab therefore does not publish a predicted 50K time from a shorter race. The chart above is pure arithmetic, finish time divided by 50 km, and it is exact. Anything beyond that would be a number with more decimal places than confidence. The methodology page sets out the limits of the model in full.

Comparing a 50K with the marathon

A 50K is 7.805 km further than a marathon, roughly 18 percent more distance. Runners coming from the road often find the first 42 km familiar and the last 8 km entirely new. To see what your marathon pace looks like over the shorter race, the marathon pace chart covers 2:00 to 7:00, and the marathon goal pages break the common targets into full splits. To plan a 50K segment by segment, the splits calculator accepts a custom distance.

Frequently asked questions

More running calculators

Last reviewed 2026-10-26. Formulas, constants and sources: methodology. Changes to any calculation are logged in the changelog.
Checked against: marathon 42.195 km (World Athletics), 1 mile = 1.609344 km.