Quick answer: match the amp rating to what your car's onboard charger will actually accept, not the biggest number on the shelf. If it tops out around 32A, the bokman Portable 32A covers it without paying for headroom you cannot use. A 40A onboard limit is the sweet spot the Grizzl-E Classic was built for. Anything at 48A, or a household planning for a second EV with different needs, calls for the ChargePoint Home Flex, since its dial covers every tier below it too.
Which Amp Tier Wins for You
ChargePoint Home Flex
Set it anywhere from 16A to 50A in the app, so one unit adapts to whatever your panel allows today and whatever EV joins the garage later.
Check it on Amazon →
Grizzl-E Classic
No app, no WiFi, no dial to set wrong. Amperage is fixed at 40A by internal DIP switches, which is plenty for most non-truck EVs.
See it on Amazon →bokman Portable 32A
A true 32A unit small enough to travel with. The right call if your car's onboard charger never asks for more than 32A anyway.
Check price on Amazon →16A, 32A, 40A, and 48A Side by Side
16A is the baseline built into most portable Level 1/2 cords; the three chargers below start at 32A and cover the range most home buyers actually shop.
| Charger | Amps | Output | Install | Smart | Price | Link |
|---|---|---|---|---|---|---|
| ChargePoint Home Flex | 16–50A adjustable | up to 12 kW | NEMA 14-50 / Hardwire | WiFi, App, Alexa, Google | $$$$ | View |
| Grizzl-E Classic | 40A fixed | 9.6 kW | NEMA 14-50 | None | $$$ | View |
| bokman Portable 32A | 32A fixed | 7.7 kW | NEMA 14-50, portable | None | $$ | View |
Price tiers are approximate. $ = under $50, $$ = $50 to 150, $$$ = $150 to 300, $$$$ = over $300. Tap any link for the current Amazon price.
Owners Across the Amp Tiers Report
Spec sheets explain the wiring; they don't explain what living with each tier feels like day to day. Here's what shows up repeatedly in verified-purchase Amazon reviews for these three, retold in our own words rather than quoted.
ChargePoint Home Flex (4.3-star verified-buyer average)
Owners describe mounting it on an existing NEMA 14-50 outlet without professional help and appreciate being able to turn the amperage dial down when a panel is tight. The recurring complaint in the lower-star reviews is app and WiFi flakiness after a firmware update, so budget a few minutes for occasional reconnects.
Grizzl-E Classic (4.6-star verified-buyer average)
Reviews read like a hardware spec sheet: buyers describe a no-frills steel box that runs cool at its full 40A draw for years without a single app to update or a password to remember. The industrial, all-metal build is the through-line across the positive write-ups, and owners who tried smart chargers first specifically call out never missing the features.
bokman Portable 32A (4.8-star verified-buyer average)
Verified buyers highlight how compact it packs down for a glovebox or trunk, and several mention using the same unit at a rental property and a primary home by simply moving it between two NEMA 14-50 outlets. The 32A ceiling is the tradeoff reviewers flag most, since it's plainly not built for a 48A-hungry truck.
Jacob’s read on amperage tiers
The temptation is to buy the biggest number since it feels like a safety margin, but a 48A circuit is not something you casually resize later. My own third install went in at 40A because both cars in the household top out there, and the extra electrical work a 60A hardwire circuit would have needed bought zero additional speed today. If you know a bigger-battery EV is joining the household within a year or two, oversizing pays for itself. If you're guessing, the plug-in 32A or 40A tier is the reversible choice, since adding a second circuit later is far simpler than downsizing one you already paid to run.
How Amperage Turns Into Charging Speed
Every Level 2 charger runs on a 240V circuit, so kilowatts are just amps multiplied by volts. A 16A charger delivers about 3.8 kW, a 32A charger about 7.7 kW, a 40A charger 9.6 kW, and a 48A charger 11.5 kW. Translating kilowatts into miles depends on the vehicle's efficiency, but as a rough guide: 16A adds about 8 to 12 miles of range per hour, 32A adds roughly 15 to 25 miles per hour, 40A adds roughly 20 to 30 miles per hour, and 48A adds roughly 25 to 38 miles per hour.
None of that matters if your EV's onboard charger caps the input lower than the wall unit can deliver. A 48A charger wired to a car with a 32A onboard limit still only pushes 32A into the battery; the car, not the charger, sets the actual ceiling. Read our 32A charger roundup if your vehicle sits at that lower cap, since paying for 40A or 48A hardware there buys nothing.
Finding Your EV's Onboard Charger Limit
Every EV has a maximum AC charging rate baked into its onboard charger, separate from whatever DC fast-charging number gets marketed. That figure is usually listed in the owner's manual or the automaker's spec page, expressed in kW. Divide by 240V to get the amp ceiling: an 11.5 kW onboard charger tops out at 48A, a 9.6 kW charger tops out at 40A, and a 7.2 to 7.7 kW charger tops out at 32A.
If you're shopping before you own the car, or comparing a household with two different EVs, our full EV charger buying guide walks through matching a single charger to mixed onboard limits without overpaying for either car.
Breaker and Circuit Sizing by Tier
Continuous 240V loads, which an EV charger is, need a breaker rated for 125% of the charger's draw under the National Electrical Code. A 32A charger needs a 40A breaker and wire rated to match. A 40A charger needs a 50A breaker, which is also what a standard NEMA 14-50 outlet is built around. A 48A charger needs a 60A breaker, and at that point most installers hardwire the connection rather than run it through a plug, since a plug-and-cord rated for continuous 48A draw is harder to source and less common in residential work.
That NEMA 14-50 vs hardwire decision has its own tradeoffs beyond just amperage; our hardwired charger comparison covers what changes when you skip the outlet entirely. Always have a licensed electrician confirm the exact breaker and wire gauge for your specific panel and run length before installation.
Which Amperage Tier to Buy
Get the bokman Portable 32A if your EV's onboard charger caps at 32A or lower, or if you split time between two locations and want one charger that travels with you.
Get the Grizzl-E Classic if your car accepts a full 40A and you have zero interest in an app, scheduling, or firmware updates. It's the tier where a fixed, no-frills unit still captures all the speed your car can use.
Get the ChargePoint Home Flex if your car accepts 48A, your panel has room for a 60A hardwired circuit, or you want one charger that can be dialed down for a smaller panel today and dialed back up if a higher-capacity EV joins the driveway.
FAQ
How We Verified Every Amp Figure Here
Every kW figure in this guide is calculated directly from volts times amps at 240V, the same math the industry uses, then cross-checked against multiple charger and EV manufacturer spec sheets rather than a single source, since real-world miles-per-hour varies by vehicle efficiency. Prices, connector type, and adjustable range for the ChargePoint Home Flex, Grizzl-E Classic, and bokman Portable 32A were re-checked against their current Amazon listings on 2026-08-03, and each pick's star rating reflects its verified-buyer average at that same check.
I'm not paid by any manufacturer and don't accept review units. That means these tiers reflect what I'd actually wire into my own garage at each amperage level, not a sponsored ranking.