How long does charging actually take?

Time to charge = energy you need (kWh) ÷ charging power (kW). With a real number attached: a car needing 30 kWh takes about 21 hours at Level 1, or about 5 hours at 24 amps on a dryer circuit, or about 3 hours at 40 amps.

But the number people ask for — time from empty to full — is almost never the number that matters. You are not driving from empty and you are not waiting for full. What matters is whether the energy you used today goes back in while the car is parked tonight, and that is a much easier bar.

Add 10-15% to every figure for charging losses, and more in cold weather when the car spends energy warming itself. These are also averages across a session — charging slows near the top of the battery's range, so the last 10% takes disproportionately longer.

Nobody charges from empty at home. Here is the same arithmetic against a normal day's driving, which is the case you are really in:

Quick picks

Ranked, with the reasoning underneath. Tap any row to jump to that write-up; tap the price to check it on Amazon. Prices come from the live layer, never from this page.

#	Product	Best for	Type	Price
1	Grizzl-E Mini Connect Portable ChargerAdjustable from 7 to 40 amps and shipped with four plug adapters, which is the closest thing to a unit that fits whatever outlet you turn out to have.	Not knowing your outlet yet	Adjustable Level 1 and 2 EVSE	Check price#ad
2	Lectron Portable Level 1 J1772 Charger (15A, NEMA 5-15)The unglamorous answer that covers most commutes: an ordinary 120V socket, overnight, and no conversation with anybody about electrical work.	An ordinary wall socket	Level 1 EVSE	Check price#ad

#1 · Not knowing your outlet yet

Grizzl-E Mini Connect Portable Charger

Adjustable from 7 to 40 amps and shipped with four plug adapters, which is the closest thing to a unit that fits whatever outlet you turn out to have.

Published specifications for the Grizzl-E Mini Connect Portable Charger, each linked to its source

Adjustable current	7A to 40A (9.6 kW maximum)source
Voltage	Automatically detects 120V (Level 1) or 240V (Level 2)source
Cable length	25 ft (7.6 m)source
Plug and adapters	NEMA 14-50 plug plus four included electrical adapterssource
Connector	J1772 or Tesla (NACS) versionssource
Enclosure	UL Type 4 / IP67 ratedsource
Certification	UL tested and certified, Energy Star certifiedsource

What those numbers mean

The adjustable current is the feature that matters to a renter, and it is not a convenience. A 30 amp dryer circuit legally supports 24 amps of continuous EV load; a unit that can be set to 24 amps can use that circuit, and a fixed 40 amp unit cannot.

25 ft of cable is nine feet more than the common 16 ft, and nine feet is frequently the difference between reaching the car and not.

IP67 and a UL Type 4 enclosure describe the unit's own weather tolerance. They say nothing about the outlet it plugs into, which is usually the part that is not weather-rated.

What it does well

• 7-40A adjustment means one unit fits a 15, 20, 30 or 50 amp circuit
• 25 ft cable is among the longest on a portable unit
• Four plug adapters included, so an outlet change does not mean a new charger
• Available with either a J1772 or a NACS connector

What it does not

• Costs meaningfully more than a fixed-amperage unit that does one job
• The bundled adapters make it easy to plug into a circuit you have not actually checked

Skip this one if: You know exactly which outlet you have, it is not changing, and you would rather put the money into a longer cable than into adjustability you will set once and never touch.

Check price on Amazon

#ad · how this is funded

#2 · An ordinary wall socket

Lectron Portable Level 1 J1772 Charger (15A, NEMA 5-15)

The unglamorous answer that covers most commutes: an ordinary 120V socket, overnight, and no conversation with anybody about electrical work.

Published specifications for the Lectron Portable Level 1 J1772 Charger (15A, NEMA 5-15), each linked to its source

Input	120V, 15A maximumsource
Output power	1.8 kWsource
Cable length	16 ftsource
Plug / connector	NEMA 5-15 plug, J1772 connectorsource
Certification	UL 2594 / UL 2231 certifiedsource
Manufacturer charge-rate claim	45+ miles of range overnightsource

What those numbers mean

1.8 kW sounds trivial next to 9.6 kW, and for a road trip it is. For a commute it usually is not: the average US driver covers well under 45 miles a day, and this replaces that overnight while the car sits anyway.

The honest ceiling is the socket, not the cable. A 15 amp household circuit shared with a refrigerator and a space heater will trip, and the fix is a different socket rather than a different charger.

This is the only category of EV charging that is genuinely invisible to a landlord. It draws less than a hair dryer and plugs into a receptacle that already exists.

What it does well

• Works with a socket that already exists, everywhere, with no permission needed
• UL 2594 and UL 2231 certified rather than a generic cordset
• Cheapest possible entry into home charging, by a wide margin

What it does not

• 1.8 kW will not recover a long driving day overnight
• 16 ft cable, and the nearest 120V socket is often not the nearest thing to the car

Skip this one if: You regularly drive more than about 45 miles a day. Level 1 will fall a little further behind every night and you will spend the difference at public chargers.

Check price on Amazon

#ad · how this is funded

1. 1Charging losses. 10-15% of what the meter records does not reach the battery.
2. 2Cold. A cold battery accepts charge more slowly and the car uses energy to warm itself. A winter overnight can return meaningfully less than the same session in summer.
3. 3The top of the range. The last 10-20% is slower by design, to protect the battery. Charging to 80% is much faster per kWh than charging to 100%.
4. 4Your car's onboard charger. A car that accepts 7.2 kW gets 7.2 kW from a 9.6 kW supply. That is the ceiling and no charger raises it.
5. 5A shared circuit pausing. With a dryer splitter, a laundry cycle pauses charging. Overnight you will not notice.

Set a departure time in the car rather than watching a percentage. Most EVs let you say "be ready at 7am," and the car works backwards from there. Once that is set, session duration stops being something you think about at all — which is the actual end state of getting home charging right.

If you want to price those sessions rather than time them, cost to charge has the formulas.