Written by Muneeb Rana · Last updated 26 October 2026
Quick answer: To measure distance driven, reset your car's trip meter at the start, or tap Start on a GPS odometer app like Speedometer PRO before you leave, then read the total when you arrive. For planning or after the fact, a map route gives a good estimate. Each method differs by a percent or two.
TL;DR
- Car trip meter: simplest.
- GPS app: works in any vehicle.
- Map route: plan before or estimate after.
- Expect 1–3% differences.
- Log purpose and date for taxes.
Measure distance driven with the car
Reset trip A before setting off and read it on arrival. It uses the car's wheel sensors, so it usually reads a touch high.
With a GPS app
Open Speedometer PRO, tap Start on the Current Trip card while parked, and drive. It shows distance, duration, average and maximum speed; finished trips go into trip history. Keep location set to precise and allow the app to keep running.
With a map
Route planners give road distance between addresses. They are good for estimates and mileage claims if your employer accepts them.
Comparing methods
| Method | Pros | Cons |
|---|---|---|
| Car trip meter | Always on | Reads slightly high; only that car |
| GPS app | Any vehicle; speed stats | Tunnels, battery |
| Map route | No device needed | Ignores detours |
For tax and expenses
Keep a log of date, start and end, distance and purpose. See mileage tracking for taxes. Speedometer PRO is not a tax product; export options are.
Comparing three methods
Your odometer counts wheel turns and can read slightly high or low depending on tyres. A GPS trip measures the path between fixes and can cut corners on winding roads. A route planner gives the planned distance, which may differ from the route you actually took. For most uses, all three agree within a few percent.
Records for reimbursement
If you claim mileage, note start and end odometer readings with dates and purpose, and keep them with any app logs.
Comparing with the odometer
It's normal for a GPS trip distance and the car's odometer to differ by a percent or two. The odometer counts wheel rotations, so tyre size and wear affect it. GPS sums straight lines between fixes, so it can cut corners on twisty roads and miss stretches in tunnels. For a fair comparison, use a long, mostly straight route with good sky view and note both figures at the start and end.
Tips
Start trips before moving; check battery; mount the phone. Use the travel time calculator for planning.
Related: Odometer guide: odometers and trip meters · Trip meter: duration, distance, average and max speed · Trip tracker: your past trips in one list · Mileage tracking for taxes · How odometers work · Road trip tracker: log every leg · Odometer app: total distance from GPS
Get Speedometer PRO on Google Play · Download on the App Store · Set it up before you move; never handle your phone while driving.
Sources
- Odometer (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
- Trip computer (Wikipedia): en.wikipedia.org (accessed 26 October 2026)
- Standard mileage rates (IRS): irs.gov (accessed 26 October 2026)
- GPS Accuracy (GPS.gov): gps.gov (accessed 26 October 2026)
FAQ
What is the easiest way to measure distance driven?
Reset your car's trip meter before you leave and read it at the end.
Can my phone measure how far I drove?
Yes. A GPS odometer app adds up distance as you travel, without needing data.
Why do the app and car disagree?
Cars usually over-read slightly, and GPS can miss distance in tunnels. A 1–3% gap is normal.
Can I measure distance after the trip?
Use a map route between your start and end points, adding any detours.
Does Speedometer PRO export trips?
. Trip history is visible in the app.