How to Measure Your Car's 0–60 Time with Your Phone

The 0–60 mph time — how long a car takes to accelerate from a standstill to 60 mph — is the classic measure of performance. You can measure your own car’s time with nothing more than your phone’s GPS. Here’s how to do it accurately and safely.

0–60 mph vs 0–100 km/h

The US and UK quote 0–60 mph; most other countries quote 0–100 km/h. They’re close but not the same: 60 mph is 96.6 km/h, so a 0–100 km/h time is typically a few tenths of a second longer than the same car’s 0–60 mph time. Use our speed converter for other speeds.

Why use GPS instead of a stopwatch?

A stopwatch relies on someone watching the car’s speedometer, which reads a few percent high— meaning you’d stop the clock before you actually reach 60. Human reaction time adds a few tenths more. A GPS timer measures true speed and starts automatically the moment you move.

How GPS 0–60 timing works

Phones report GPS speed about once per second. That’s too coarse to read a 0–60 time directly from the nearest sample, so good apps interpolate: they estimate the exact moment you crossed each speed using the readings on either side. The Speedometer iPhone app does this for 0–30 mph, 0–60 mph, and 0–100 km/h splits and keeps your personal bests.

Step-by-step

1. Choose a safe, legal place. A closed course, drag strip, or private road is ideal. Never test on public roads where 60 mph is unsafe or illegal, and never with other traffic or pedestrians around.
2. Mount your phone securely with a view of the sky. Loose phones slide under acceleration.
3. Wait for a strong GPS fix — under about 10–15 meters of accuracy.
4. Come to a complete stop and arm the timer.
5. Accelerate smoothly and fully. The timer starts when you begin moving.
6. Run it more than once, ideally in both directions on the same stretch, and average the results to cancel out slope and wind.

What affects your result

• Slope. Even a gentle downhill makes a big difference. Test on level ground.
• Temperature and altitude. Engines make less power in hot air and at high altitude.
• Tires and surface. Cold tires and dusty or wet surfaces cause wheelspin.
• Weight. Passengers and luggage slow you down.
• Rollout. Some magazines subtract the first foot of movement (“one-foot rollout,” a drag-strip convention), which makes published times a little quicker than a true standing start.
• GPS quality. Tall buildings or trees can degrade accuracy — open areas give the best data.

Typical 0–60 times

These are broad ranges; exact numbers vary widely by model and powertrain.

Safety first

Acceleration testing belongs on a closed course. Obey every speed limit, never test with passengers who haven’t agreed to it, and never interact with your phone while driving.