How Many Ways Can You Measure Tesla SoH — And Which Is Right for You?
Three ways to measure Tesla battery State of Health — the in-car screen, Scan My Tesla, and VoltValue. Pros, cons, and which is right for you.
There are three common ways to measure your Tesla's State of Health (SoH). Each has trade-offs in effort, cost, accuracy, and — crucially — whether the result can be shared with a buyer or finance company. Here's how they compare.
Method 1: The car's own screen
Tesla doesn't show SoH directly on the dashboard. The closest you can get is charging the battery from 0% to 100% and comparing the displayed energy added to the original pack size. It works, but the cost is real:
- Requires a full 0→100% charge cycle (10+ hours at home)
- Gives you a single % snapshot at that moment — no trend
- Can't be shared with a buyer or finance company in any verifiable way
- Stresses the battery (sitting at 100% is the worst state for NMC)
Good for a personal sanity check. Not useful for selling, financing, or tracking over time.
Method 2: Scan My Tesla (OBD2)
Scan My Tesla is a third-party app that reads raw values directly from the car's Battery Management System (BMS) via an OBD2 Bluetooth adapter. You see what the BMS itself is reporting — nominal full pack, current pack, cycle count, individual cell voltages, and more.
- Requires buying an OBD2 adapter (~฿300 and up) and installing it in the car
- Read on-demand any time — extremely detailed
- Output is a screenshot inside an app — no verifiable, signed report
- A buyer has no way to know the screenshot is real or current
Best for enthusiasts and technicians who want to see what the BMS is doing under the hood. Not built for sharing or third-party verification.
Method 3: VoltValue
VoltValue connects directly to your car via Tesla's official Fleet API. Once connected, it collects daily telemetry automatically at 02:00 UTC when the car is awake — no equipment to buy, no manual charging cycles, no daily action required.
- No hardware to buy
- Automatic daily measurement — up to 180 days of history
- SoH is a median across many days — stable, not affected by one bad reading
- Issues a VoltValue Passport — shareable link + QR code, publicly verifiable
- Designed for buyers, sellers, finance companies, and dealerships
→ How VoltValue calculates SoH
Comparison at a glance
| Car screen | Scan My Tesla | VoltValue | |
|---|---|---|---|
| Hardware needed | None | OBD2 adapter (~฿300+) | None |
| Effort per reading | 10+ hour charge | Plug in + open app | Zero — automatic |
| Historical trend | No | Manual only | 180 days, automatic |
| Shareable / verifiable | No | Screenshot only | Passport + QR verify |
| Best for | Personal check | Enthusiasts, techs | Buyers, sellers, banks |
Which is right for you?
Just curious about your own car? The car screen works for an occasional snapshot. Scan My Tesla goes deeper if you enjoy the detail.
Selling or buying a Tesla? Use VoltValue. A buyer can't verify a screenshot — they can verify a Passport. A bank or finance company needs a third-party, time-stamped report, not a number from the seller's app.
Want to learn the fundamentals? → What is State of Health (SoH)?