Speed Distance Time Calculator

How to Use This Calculator

1. Select what you want to Solve For (Speed, Distance, or Time).
2. Enter the other two known values.
3. For time, enter hours and additional minutes separately.
4. Use the Find Speed, Find Distance, or Find Time tabs for dedicated solvers.
5. The Professional tab adds pace, fuel needed, stops, and average speed across two road segments.

Formula

Example

Frequently Asked Questions

• What is the speed distance time formula? ▼
  Speed, distance, and time are related by three rearrangements of the same formula: Speed = Distance ÷ Time, Distance = Speed × Time, and Time = Distance ÷ Speed. Select the variable you want to find (the unknown) and enter the other two. Example: a car travels 150 miles in 2.5 hours → Speed = 150 ÷ 2.5 = 60 mph. Units must be consistent: if distance is in km and time is in hours, the result is km/h.
• How do I convert mph to km/h? ▼
  Multiply miles per hour (mph) by 1.60934 to get kilometers per hour (km/h). For example, 60 mph = 60 × 1.60934 ≈ 96.56 km/h, and 100 km/h = 100 / 1.60934 ≈ 62.14 mph. Other useful conversions: 1 m/s = 3.6 km/h = 2.237 mph. To convert km/h to mph, divide by 1.60934. The calculator accepts both mph and km/h and converts automatically between units in the results.
• How do I calculate travel time? ▼
  Use Time = Distance ÷ Speed. For 240 miles at 60 mph: Time = 240 ÷ 60 = 4 hours. For 350 km at 100 km/h: Time = 350 ÷ 100 = 3.5 hours = 3 hours 30 minutes. To convert decimal hours to minutes, multiply the decimal part by 60: 3.5 hours = 3 hours and 0.5 × 60 = 30 minutes. The calculator outputs the result in both decimal hours and in hours plus minutes for readability.
• What is pace? ▼
  Pace is the inverse of speed — it measures how long it takes to cover a unit distance, typically used by runners and cyclists. Pace (min/mile) = 60 ÷ Speed (mph), or Pace (min/km) = 60 ÷ Speed (km/h). At a speed of 6 mph, pace = 60 ÷ 6 = 10 min/mile. At 12 km/h, pace = 60 ÷ 12 = 5 min/km. Pace is useful for race planning: to finish a 5K in 25 minutes, you need a pace of 25/5 = 5 min/km = 12 km/h.
• How do I find average speed for two segments? ▼
  Average speed = Total Distance ÷ Total Time — not the arithmetic average of the two speeds. This is a common mistake. Example: drive 60 miles at 60 mph, then another 60 miles at 30 mph. Time for segment 1 = 1 hour; segment 2 = 2 hours. Total distance = 120 miles, total time = 3 hours. Average speed = 120 ÷ 3 = 40 mph (not 45 mph, the arithmetic average). The slower segment dominates because you spend more time in it. This is the harmonic mean of the two speeds for equal distances.

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