Pace and speed from distance and time.
Free to use, no sign-up required. Running Pace is one of 198 tools built into Xenition, alongside a chat that can use them for you.
Works out your running pace and speed from a distance and a finish time, and predicts what the same pace would give you over 5K, 10K, a half marathon and a marathon.
Pace is total seconds divided by distance, rounded to the nearest second. The other unit uses 1 mile = 1.60934 km, and speed is distance divided by hours. Race predictions multiply your pace per km by 5, 10, 21.0975 and 42.195.
10 km in 50:00 is 3,000 seconds ÷ 10 = a 5:00 min/km pace, which is 8:03 min/mi and 12.0 km/h. Held evenly, that predicts 25:00 for 5K, 1:45:29 for a half marathon and 3:30:59 for a marathon.
The prediction assumes you hold today’s pace for the whole distance on flat ground. Most runners slow over longer races, so treat it as the pace you would need, not the time you will get.
Multiply the seconds per km by 1.60934. A 5:00 min/km pace is 300 × 1.60934 = 483 seconds, or 8:03 min/mi.
You do not have to open Running Pace to use it. Ask Xenition in plain language and it runs the right tool, then carries the answer into whatever you are working on — a document, a spreadsheet, a deck.