EV maths,
worked out.

Real range instead of marketing range. Charge times that include the taper. Pack designs, wire gauges and running costs. Free tools that show their formulas — because a number you cannot check is just a rumour.

  • 14 free calculators
  • no signup
  • no ads
  • everything runs in your browser
Live exampleNinebot Max G30 · 80 kg rider
41.6km

Plan on 33.3 km with a 20% reserve, or 16.6 km each way.

Consumption
11.9Wh/km
Usable energy
496Wh
Ride time
2 h 5 min
Pack size
551Wh

Four kinds of question

Everything on this site answers one of them: how far it goes, what the battery is doing, what it costs, or how to build it without setting fire to anything.

Cost & Emissions

What a charge costs, what a car costs, and the carbon you skip.

Build & Wiring

Pack layout, motor winding, conductor sizing — for people with a soldering iron.

Start here

Six good places to start, from buying decisions to build maths.

How the tools work

No accounts, no uploads, no waiting. Type, read, ride.

  1. Enter what you know

    Battery voltage, amp-hours, your weight, the hill outside your door. Presets for popular scooters fill it in if you would rather not look anything up.

  2. Watch the gauge move

    Results update as you type — no submit button. Every tool shows the secondary numbers that explain the headline one, so you can see which input is hurting you.

  3. Check the working

    The formula and the constants sit right under each calculator. Disagree with a coefficient? Change the input and watch the result follow.

Physics, not vibes

The performance tools use standard vehicle dynamics — rolling resistance, aerodynamic drag and gradient — with coefficients calibrated against measured scooter consumption, not scaled down from bicycle data. The battery tools follow published lithium-ion charging behaviour, including the constant-voltage taper everyone else ignores.

Where a number is uncertain, the tool says so. Where a manufacturer claim is optimistic, the tool says that too.

  • Nothing leaves your device
  • Formulas published on every page
  • Calibrated against real consumption data
  • No ads, no signup, no upsell

Longer reads

The background a calculator cannot fit into a readout.

Before you ask

Are these calculators free?

Yes — all fourteen, with no account, no email and no usage limit. They run entirely in your browser, so nothing you type is sent to a server.

How accurate are the results?

The range, speed and hill tools are built on standard vehicle dynamics — rolling resistance, aerodynamic drag and gradient — calibrated against measured scooter consumption. For steady riding on known terrain they typically land within 10–15% of reality. Treat every result as a planning figure, not a guarantee.

Do they work for e-bikes and electric cars too?

Mostly, yes. The battery, charging, cost and wiring tools are chemistry and electrical maths that apply to any EV. For the range and speed tools, change the riding position to suit a seated rider and the physics carries over unchanged.

Why should I trust the numbers?

Because every tool shows its formula on the page, along with the constants it assumes. You can check the arithmetic yourself, or substitute your own coefficients if you have measured them.

Do you store the values I enter?

Only in your own browser, so a tool remembers your setup the next time you visit. The values themselves are never transmitted — Google Analytics counts page visits but never sees what you type — and clearing site data removes the saved inputs.

Which calculator should I start with?

If you are buying a scooter, start with the range calculator and the watt-hours calculator. If you already own one, the charge time and battery health tools tell you the most about what you have. If you are building a pack, start with the pack calculator and the wire gauge calculator.

Fourteen calculators. None of them will flatter your scooter.

Range, charge time, watt-hours, pack layout, wire gauge, running cost and emissions — free and instant.