# 5K Pace Calculator Calculate your 5K pace per mile and per km from a target finish time. Get race predictions for 10K, half marathon, and marathon using the Riegel formula. ## What this calculates Whether you are training for your first 5K or chasing a PR, knowing your target pace makes all the difference. Enter your goal finish time to see the per-mile and per-km pace you need to hit, plus predicted finish times for longer races. ## Inputs - **Target Time (Minutes)** — min 0, max 59 - **Target Time (Seconds)** — min 0, max 59 ## Outputs - **5K Finish Time** — formatted as text — Your target 5K time (3.107 mi / 5 km) - **Pace per Mile** — formatted as text — Required pace per mile - **Pace per Km** — formatted as text — Required pace per kilometer - **Average Speed** — Average running speed - **Race Predictions (Riegel)** — formatted as text — Predicted finish times for longer distances ## Details A 5K (5 kilometers) is 3.107 miles, making it one of the most popular race distances worldwide. Here are some common 5K benchmarks and the paces needed to hit them: - **Sub-20:00**: 6:26 /mi (4:00 /km) -- competitive runner territory - **Sub-25:00**: 8:03 /mi (5:00 /km) -- strong recreational runner - **Sub-30:00**: 9:39 /mi (6:00 /km) -- solid fitness level - **Sub-35:00**: 11:16 /mi (7:00 /km) -- good beginner goal The race predictions use the Riegel formula (T2 = T1 x (D2/D1)^1.06), which accounts for the natural pace slowdown that occurs at longer distances. A 25-minute 5K runner can expect roughly a 52-minute 10K, a 1:55 half marathon, and a 4:01 marathon at equivalent fitness. Keep in mind that these predictions assume consistent training at the longer distance. A fast 5K does not automatically translate to a fast marathon without the endurance base to support it. The Riegel formula is most accurate for predicting distances within 2-3x of your input distance. For 5K training, a typical week might include 3-4 easy runs, one speed workout (intervals or tempo), and one longer run of 5-8 miles. Most 5K improvement comes from consistent weekly mileage rather than any single workout. ## Frequently Asked Questions **Q: What is a good 5K time?** A: A good 5K time depends heavily on age, sex, and fitness level. For adult men, sub-25:00 puts you ahead of most recreational runners. For adult women, sub-28:00 is a strong result. Competitive club runners typically aim for sub-20:00 (men) or sub-23:00 (women). For beginners, finishing a 5K at any pace is a genuine accomplishment. The average 5K finish time across all runners is around 28-35 minutes. **Q: How accurate are the race predictions?** A: The Riegel formula is reasonably accurate for predicting the next distance up (5K to 10K, for example) if you have trained appropriately for both distances. Predictions get less reliable for large jumps, like predicting a marathon from a 5K. The formula assumes equivalent training, so a 5K specialist without marathon training will likely run slower than the prediction. Use these as rough targets and adjust based on your actual training. **Q: How can I improve my 5K time?** A: The biggest improvements come from (1) increasing weekly mileage gradually, which builds your aerobic base, (2) adding one speed workout per week such as 400m or 800m repeats at faster-than-race pace, and (3) running most of your miles at easy pace (about 90 seconds slower than 5K pace). Consistency over months matters more than any single hard workout. Most runners can drop 2-5 minutes off their 5K with 8-12 weeks of structured training. **Q: Should I run the whole 5K at the same pace?** A: Even pacing is the most efficient strategy for a 5K. Start at your goal pace (or even a few seconds slower for the first kilometer), settle into rhythm in the middle, and use any remaining energy in the final kilometer. Starting too fast almost always leads to a slower overall time because the oxygen debt from the first mile carries through the rest of the race. --- Source: https://vastcalc.com/calculators/health/five-k-pace Category: Health & Fitness Last updated: 2026-04-08