Running Pace Calculator
Calculate Your Running Pace, Time, or Distance
Whether you're training for your first 5K or targeting a marathon PR, understanding pace is the foundation of effective running. This calculator solves for any one of the three core variables — pace, finish time, or distance — when you know the other two.
How to Use This Calculator
Select what you want to solve for from the dropdown: Pace (if you know distance and time), Finish Time (if you know distance and target pace), or Distance (if you know time and pace). Enter the known values and hit Calculate. Results show pace in both min/mile and min/km, speed in mph and km/h, and the full distance and time for reference.
Pace vs. Speed — Understanding the Difference
Runners use pace (time per unit distance); most other sports use speed (distance per unit time). They're reciprocals of each other:
An 8:00/mile pace equals 7.5 mph. A 10:00/mile pace equals 6 mph. Converting between the two helps when using treadmills (which display speed) or GPS watches (which display pace).
Real-World Example
Using the defaults — 5 miles in 40 minutes (solving for pace):
- Pace: 40 min ÷ 5 mi = 8:00/mile
- Pace in km: 8:00/mi ÷ 1.609 = 4:58/km
- Speed: 60 ÷ 8 = 7.5 mph
Using that 8:00/mile pace to predict race finish times:
- 5K (3.107 mi): 24:51
- 10K (6.214 mi): 49:42
- Half marathon (13.11 mi): 1:44:53
- Full marathon (26.22 mi): 3:29:46
Common Race Distances
- 5K — 3.107 miles. Most popular race distance worldwide. Average finish time: ~30–35 minutes for recreational runners.
- 10K — 6.214 miles. A step up requiring more endurance. Average: ~60–70 minutes.
- Half marathon — 13.11 miles. A serious distance goal for many runners. Average: ~2:10–2:30.
- Full marathon — 26.22 miles. The classic distance. Average finish time: ~4:30–5:00. World record: 2:00:35 (Kelvin Kiptum, 2023) at ~4:35/mile.
Training Pace Zones
Effective training uses different paces for different workouts. Roughly speaking:
- Easy/recovery runs (60–70% max HR) — about 2:00/mile slower than your 5K race pace. Conversational. Should make up ~80% of weekly mileage.
- Long runs (65–75% max HR) — similar to easy pace, extended duration. Builds aerobic base and fat-burning efficiency.
- Tempo runs (85–90% max HR) — "comfortably hard." About 20–30 seconds/mile faster than marathon race pace. Builds lactate threshold.
- Intervals (95–100% max HR) — short, hard efforts at 5K pace or faster. Builds VO2 max and running economy.
The 80/20 rule — 80% easy, 20% hard — is the most evidence-backed approach to training volume distribution for recreational and competitive runners alike.
Frequently Asked Questions
What is a good running pace for a beginner?
A comfortable beginner pace is typically 10–12 minutes per mile (about 5–6 mph). The most important thing for new runners is building consistency and aerobic base — pace matters far less than running regularly. If you can hold a conversation while running, you're at an appropriate easy pace.
How do I predict my race time from a training run?
Enter your training distance and time to find your pace, then use that pace to solve for finish time at your target race distance. Keep in mind that race conditions (adrenaline, competition, course terrain, weather) affect actual performance. Many runners find they run 5–10% faster in races than training runs of the same distance.
What pace do I need to qualify for Boston?
Boston Marathon qualifying times vary by age and gender. For men 18–34, the qualifying time is 3:00:00 (a 6:52/mile pace). For women 18–34, it's 3:30:00 (8:01/mile). Older age groups have progressively more generous cutoffs. Note that qualifying time only makes you eligible to enter — actual acceptance requires running faster than the cutoff year due to oversubscription.
How much does pace slow over a marathon vs. a 5K?
Most runners slow by 45–75 seconds per mile from 5K pace to marathon pace. An 8:00/mile 5K runner might target 8:45–9:15/mile for a marathon. The longer the race, the more critical pacing strategy becomes — going out too fast is the most common marathon mistake.
How do I convert my pace between miles and kilometers?
To convert min/mile to min/km: divide by 1.609. To convert min/km to min/mile: multiply by 1.609. An 8:00/mile pace = 4:58/km. A 5:00/km pace = 8:03/mile. This calculator shows both automatically once you calculate.