What is your Tesla’s battery actually holding?

Connect in twenty seconds. See your real capacity, your degradation, and where you rank.

Check my battery — free
  • Free — no account needed to get your number
  • You sign in on Tesla’s page — never a password here
  • Delete your data in one click

What you get

What we can and can’t touch

What counts as normal degradation

Every pack loses capacity. The real question is whether yours is losing it faster than it should:

OdometerTypical remaining capacityWhat it means
0–25k mi95–98%The fast early drop. Alarming to watch, completely normal.
25k–50k mi92–96%The curve is already flattening out.
50k–100k mi88–93%Slow, steady. Most cars live here.
100k–150k mi85–90%Still far above the warranty floor.
150k mi+80–88%Tesla's 8-year warranty floor is 70%.

Commonly observed across large owner-reported datasets — context, not a guarantee. Your own result is measured from your car.

How it works

  1. Authorise on Tesla's own login page.
  2. We read the car once: charge level, rated range, odometer, configuration.
  3. Rated range ÷ charge level = your range at 100%, compared against the EPA figure your model year shipped with.
  4. We discard the token. Only the numbers remain.

Can't identify your exact configuration? We show the measured numbers and refuse to guess a degradation percentage — a wrong baseline invents degradation that isn't there.

Questions

How much Tesla battery degradation is normal?
Most packs lose their first few percent quickly, then flatten out. Roughly 5% in the first 25,000–50,000 miles is ordinary, and the curve bends: the second 5% takes far longer than the first. Tesla's own warranty standard is that the pack retains at least 70% capacity over 8 years, so anything comfortably above that at normal mileage is not a problem.
Does this need my Tesla password?
No, and you should never give your Tesla password to any third-party site. You sign in on Tesla's own login page, and Tesla hands us a read-only token. We never see your credentials.
Can this site unlock, drive, or locate my car?
No. We request exactly one permission — vehicle information — and deliberately do not request command access or location access. Sending a command to a modern Tesla also requires a virtual key physically added in your Tesla app, which we never ask for.
Do you store my Tesla login?
No. We read the car once, compute the numbers, and discard the token. There is no stored refresh token, so this site cannot reach your car again until you choose to reconnect.
Why is my range lower than the EPA number even at 100%?
Two different things get confused here. The rated range on your screen is a fixed EPA figure multiplied by your pack's current capacity — it drops as the pack ages. Your actual miles also depend on speed, temperature, terrain and tyres, which is why a healthy pack can still under-deliver on a cold motorway run.
Is a lower number worth worrying about?
Usually not on its own. Degradation is gradual and mostly cosmetic until it affects your daily use. A sudden step change, or a figure far below other cars of the same age and mileage, is the thing worth investigating — which is exactly what the percentile here is for.

Independent fan project. Not affiliated with, endorsed by, or connected to Tesla, Inc. Figures are estimates derived from your vehicle's own reported data and are not a substitute for a service diagnosis.

/// The Daily Verdict
Know the moment a prediction lands — or doesn't.
One email a day, only when something changes: a new promise, a blown deadline, a goalpost move, or a rare on-time delivery. No spam, instant unsubscribe.