Pace

1. **Choose your unit system** — select miles (min/mile, mph) or kilometers (min/km, km/h) to match your training log or race course.
2. **Pick what you want to calculate** — choose Pace, Finish Time, or Speed as your target output.
3. **Enter the two known values** — for example, input your Distance (e.g., 13.1 miles) and your Total Time (e.g., 2 hours 10 minutes) to find pace.
4. **Read your result** — the calculator displays pace in min/mi or min/km, speed in mph or km/h, and total time in hh:mm:ss format.
5. **Adjust and experiment** — change your goal time to see what pace you need, or enter a pace to project a finish time for any race distance.

Pace = T / D   |   T = Pace × D   |   Speed = D / T

• T — Total elapsed time for the run or race, expressed in minutes (or hours:minutes:seconds converted to decimal minutes).
• D — Total distance covered, expressed in miles or kilometers depending on the desired pace unit.
• Pace — Time required to cover one unit of distance — typically expressed as minutes per mile (min/mi) or minutes per kilometer (min/km).
• Speed — Distance covered per unit of time — expressed as miles per hour (mph) or kilometers per hour (km/h). Calculated as Speed (mph) = 60 / Pace (min/mi).

Pace = T / D = 130 min ÷ 13.1 mi = 9.924 min/mi ≈ 9:55 per mile
Speed = 60 / 9.924 = 6.05 mph
Verification: 9.924 min/mi × 13.1 mi = 130.0 minutes ✓

Result: Pace ≈ 9:55 per mile | Speed ≈ 6.05 mph | Finish Time = 2:10:00

A finish time of 2 hours and 10 minutes for a half marathon (13.1 miles) corresponds to a pace of approximately 9 minutes 55 seconds per mile, or a running speed of about 6.05 miles per hour. To run faster, you need to lower your per-mile pace (a smaller number); to run slower, your pace number increases. Use this as a benchmark when planning your training runs or setting a goal corral at your next race.

Understanding Running Pace

Pace vs. Speed Pace and speed express the same motion from opposite perspectives. Speed asks how far in a given time (e.g., 6 mph), while pace asks how long for a given distance (e.g., 10 min/mile). Runners typically use pace because it directly answers the question "am I on track to finish in my goal time?"

Common Race Distances & Their Pace Demands | Race | Distance | Sub-2-hour pace needed | |------|----------|------------------------| | 5K | 3.11 mi | 9:41/mi | | 10K | 6.21 mi | 9:41/mi | | Half Marathon | 13.1 mi | 9:09/mi | | Marathon | 26.2 mi | 4:35/mi (sub-4 hrs) |

Negative Splits Running a negative split means your second half is faster than your first. Research in competitive running suggests this is the most common strategy among elite marathoners and often leads to better overall performance for recreational runners too.

Training Zones & Pace Your easy run pace is typically 60–90 seconds per mile slower than your race pace. Tempo runs are typically 20–30 seconds per mile slower than your 10K race pace. Using the pace calculator to set these zones helps structure effective training weeks.

Treadmill Speed Conversion Treadmills display speed in mph (or km/h), not pace. The conversion is: Pace (min/mi) = 60 ÷ Speed (mph). For example, a treadmill set to 6.0 mph equals a 10:00/mile pace.

Disclaimer: This calculator is for educational and training-planning purposes only. It is not a substitute for professional coaching or medical advice. Consult a qualified healthcare provider before starting or significantly changing a running program, especially if you have any cardiovascular or musculoskeletal health concerns.

• **Mixing unit systems** — entering distance in kilometers but selecting min/mile as the output unit will produce an incorrect pace. Always confirm your distance unit matches your pace unit.
• **Forgetting to convert time to decimal** — entering 1:30 as '1.30' instead of 90 minutes (1.5 hours) is a common error. Use the hh:mm:ss input fields rather than converting manually.
• **Confusing pace with speed** — a lower pace number (e.g., 8:00/mile) means you are running *faster*, which is the opposite of how speed works (higher mph = faster).
• **Using course distance vs. GPS distance** — GPS watches often record slightly more than the official race distance. Use the official certified distance for accurate race pace calculations.
• **Not accounting for elevation** — pace on a hilly course will be slower than on a flat course. Flat-course pace from this calculator won't reflect effort on hilly terrain without an effort-adjusted pace formula.

• Metabolic Equivalent of Task (MET) and Running Energy Expenditure — American Council on Exercise (ACE)
• Physical Activity Guidelines for Americans, 2nd Edition — U.S. Department of Health and Human Services
• ACSM's Guidelines for Exercise Testing and Prescription, 11th Edition — American College of Sports Medicine (ACSM)

Only sources that have been reviewed are shown. Unverified citations are never published.