NOCO GBX45 vs GB40

These two get compared constantly because they look like the same product a few years apart, and in the way that matters most — will it start my car — they very nearly are. The differences are all in how the pack lives with you between emergencies.

Quick picks

Tap any row to jump to the full write-up. Scoring criteria are published in full on our methodology page.

#	Product	Best for	Our read	Price
1	NOCO Boost X GBX45 Buy this if you travel with it	Travel and carry-on use	48-minute recharge, 60 W USB-C in and out	Check price on Amazon→ #ad Affiliate link · We show no price here; Amazon shows the current one
2	NOCO Boost Plus GB40 Buy this if it lives in the trunk	Most cars and small SUVs	Same job, lower price, 20 starts per charge	Check price on Amazon→ #ad Affiliate link · We show no price here; Amazon shows the current one
3	NOCO Boost Plus GB50 Buy this if you want amps instead	V6 and small V8 gas engines	1,500 A and 35 Wh for the same kind of money	Check price on Amazon→ #ad Affiliate link · We show no price here; Amazon shows the current one

It refills in under an hour. NOCO states a complete recharge in 48 minutes over 60-watt USB-C, and that five minutes of charge is enough to jump start. The GB40 recharges from a powered USB port in about three hours at 2.1 amps. On a trip, where the pack may have to work twice in two days, that is the whole argument.

It takes the charger you already carry. USB-C Power Delivery in and out means a laptop brick refills it and it refills a laptop — one cable, no proprietary wall wart. The travel roundup is built around exactly this, and the power-bank comparison covers what the output side is honestly good for.

It is slightly lighter and slightly stronger. 2.16 lb against 2.45 lb, 1,250 amps against 1,000, and a diesel rating that goes to 4.0 liters rather than 3.0. None of these is decisive on its own, but they all point the same way.

Cost per start. The GB40 is the cheaper pack and NOCO publishes up to 20 jump starts on a single charge. For a pack that lives in a trunk and might be used once a year, recharge speed is irrelevant — it recharges overnight on the kitchen counter either way.

It is the better-understood product. The GB40 has been the default recommendation in this category for years, which means replacement clamps, cases and accessories are everywhere. The full GB40 review goes through it in detail, and the GBX45 review does the same for the newer pack.

It is fine in a hot car — within limits. Both are lithium and both have the same storage caveat, which has nothing to do with which one you pick. Jump starter storage and heat covers where the pack should actually live.

If what you actually want is more starting margin rather than faster charging, the GB50 is the pack to look at: 1,500 peak amps, 35 watt-hours, 7.0 liters gas and 4.5 liters diesel, for a quarter of a pound more than the GB40. It has no USB-C Power Delivery and no 48-minute recharge, so it is the opposite trade to the GBX45 — raw capability instead of convenience.

Put the three in a line and the choice becomes clear. The GB40 is the baseline. The GBX45 spends the premium on packability and speed. The GB50 spends it on amps. The portable jump starter roundup places all three against the rest of the field.

1. Buy this if you travel with it

NOCO Boost X GBX45

NOCO · Best for travel and carry-on use

The travel pick: 1,250 peak amps at 2.16 lb with USB-C Power Delivery in and out, so it recharges from the same brick as your laptop.

Published specifications

Peak amps

1,250 A source

Internal battery

31 Wh lithium-ion source

Gas engine rating

Up to 6.5 liters source

Diesel engine rating

Up to 4.0 liters source

Weight

2.16 lb (0.98 kg) source

USB-C output

Up to 20 V / 3 A Power Delivery source

Water resistance

IP65 with ports closed source

Warranty

1-year hassle-free source

What works

• +Lightest pack in the range at 2.16 lb, and 31 Wh means no airline paperwork
• +USB-C Power Delivery both directions — one cable covers the pack, phone and laptop
• +More gas headroom than the GB40 (6.5 L against 6.0 L) in a lighter body

What does not

• −The IP65 rating only holds with the port covers closed — worth remembering in the rain
• −The 4.0 L diesel ceiling is not enough for a full-size diesel pickup

Skip it if

Not the right pack for a diesel truck, and not the cheapest way to cover a small commuter — its premium buys packability, not amps.

Check price on Amazon→

#ad Affiliate link · We show no price here; Amazon shows the current one

Raw specifications: NOCO’s own page for the NOCO Boost X GBX45.

2. Buy this if it lives in the trunk

NOCO Boost Plus GB40

NOCO · Best for most cars and small suvs

The default answer for a four- or six-cylinder car: 1,000 peak amps, 24 watt-hours, and light enough that it actually stays in the trunk.

Published specifications

Peak amps

1,000 A source

Internal battery

24 Wh lithium-ion source

Gas engine rating

Up to 6.0 liters source

Diesel engine rating

Up to 3.0 liters source

Weight

2.45 lb (1.11 kg) source

Water resistance

IP65 source

Flashlight

100 lumens source

Warranty

1-year hassle-free source

What works

• +24 Wh sits far under the 100 Wh carry-on threshold, so flying with it needs no airline approval
• +2.45 lb and pocketable — the size that decides whether a tool is still in the trunk six months later
• +IP65 enclosure, so a wet shoulder in the rain is not a problem
• +Reverse-polarity protection means a backwards clamp does not spark

What does not

• −1,000 peak amps runs out of headroom above a 6.0 L gas engine
• −The 3.0 L diesel ceiling rules out most modern diesel pickups
• −24 Wh is a small reserve — it is a jump starter, not a power bank substitute

Skip it if

Not the one to buy if you drive a diesel pickup or a big V8. You would be at the edge of its rating on a cold morning, which is exactly when you want margin.

Check price on Amazon→

#ad Affiliate link · We show no price here; Amazon shows the current one

Raw specifications: NOCO’s own page for the NOCO Boost Plus GB40.

3. Buy this if you want amps instead

NOCO Boost Plus GB50

NOCO · Best for v6 and small v8 gas engines

The middle rung: 1,500 peak amps and 35 watt-hours for a quarter-pound more than the GB40, which is the cheapest headroom in the range.

Published specifications

Peak amps

1,500 A source

Internal battery

35 Wh lithium-ion source

Gas engine rating

Up to 7.0 liters source

Diesel engine rating

Up to 4.5 liters source

Weight

2.71 lb (1.22 kg) source

Water resistance

IP65 source

Flashlight

200 lumens source

Warranty

1-year hassle-free source

What works

• +A full liter more gas headroom than the GB40 for 0.26 lb more weight
• +35 Wh still clears the 100 Wh carry-on limit with room to spare
• +Doubles the flashlight output over the GB40 at 200 lumens

What does not

• −Overlaps awkwardly with the GBX45, which is lighter and charges over USB-C
• −Still short of the 6.0 L diesel rating a modern diesel pickup wants

Skip it if

Skip it if convenience matters more than amps — the GBX45 is lighter and takes USB-C Power Delivery, and the GB50's edge is raw current.

Check price on Amazon→

#ad Affiliate link · We show no price here; Amazon shows the current one

Raw specifications: NOCO’s own page for the NOCO Boost Plus GB50.