Charge Time Calculator
Estimate how long a full charge takes from your battery's capacity and your charger's output current.
Estimated charge time (from empty)
This is the constant-current phase, roughly capacity ÷ (charger current × efficiency). The last ~20% charges more slowly as the pack tapers in its constant-voltage “trickle” phase, so a full 100% charge takes a little longer than this figure implies.
Why a bigger charger isn’t always the answer
Charge time falls almost linearly as charger current rises — a 2A charger fills a pack roughly twice as fast as a 1A one. But the pack and its charging circuit have their own current limits, and pushing more current than they're designed for runs them hotter and wears the cells faster. A faster charger is only safe if the device is rated for it.
The other half of the picture is the taper at the top. Because the constant-voltage phase slows the last stretch, going from empty to 80% is quick, but squeezing out the final 100% takes disproportionately longer — worth knowing when you're timing a charge before a ride.
Frequently Asked Questions
How long should a hoverboard take to charge?
It depends on the pack size and the charger. As a rough guide, a small hoverboard with a low-amp charger often takes a few hours from empty, while a large scooter or EUC pack on a modest charger can take much longer. The tool estimates it as capacity in amp-hours divided by the charger's effective output current.
Why isn't it just capacity divided by charger current?
That's the core of it, but no charger or pack is perfectly efficient — some energy is lost as heat in the charger and the cells. This tool derates the charger's current by an efficiency factor (about 0.9 by default) so the estimate lands closer to reality than the pure arithmetic would.
What is the trickle or constant-voltage phase?
Lithium packs charge in two stages. First is constant current, where the charger pushes its full rated current and the pack fills quickly and roughly linearly — that's the part this tool estimates. Near full, it switches to constant voltage and the current tapers off, so the last 20% or so charges noticeably more slowly than the first 80%.
Is it bad to leave it charging overnight?
A quality charger stops or holds once the pack is full, but leaving any lithium device charging unattended for long periods carries a small risk, so many manufacturers advise against it. Charging while you're around to unplug it, and not leaving it plugged in for days, is the cautious habit. Always follow the guidance that came with your device.
Should I charge to 100% every time?
For maximum lifespan, many riders avoid sitting at a full 100% charge for long and don't routinely run to empty either — keeping the pack in a middle band is gentler on the cells. If you need the full range for a specific ride, charging to 100% shortly before you leave is a reasonable compromise.
Estimates only — real charge time varies with battery age, temperature, and charger behaviour. Ride safely, wear a helmet, and follow your device's charging guidance and local law.