Rank #1 in Best Jump Starter 2026: 10 Car Battery Boosters Ranked
NOCO Boost GB40 1000A UltraSafe Jump Starter Power Pack
Price and rating as shown on Amazon when we collected them. Both change.
The NOCO Boost GB40 is a 1000-amp lithium jump starter, and it takes first place in our jump starter ranking. Everything on this page comes from its Amazon listing rather than from our own testing: the price, the specification table, the spread of its customer ratings, and two review quotes copied word for word.
Two figures reward a closer look. The title sells the GB40 as a portable power bank, while the specification table puts its battery at 2,150mAh, which is a top-up rather than a full phone charge. And NOCO states up to 20 starts per charge on engines up to 6.0 litres of petrol, a figure worth reading next to the ratings breakdown below rather than on its own. Both come from the listing itself, so you can check either one.
How those 126,359 ratings break down
An average hides its own shape. This is the spread behind the 4.5 stars.
Specification
Exactly as published on the Amazon listing, field for field.
| Brand | NOCO |
|---|---|
| Model number | GB40 |
| Manufacturer part number | GB40 |
| Peak output current | 1000 Amps |
| Amperage | 1000 Amps |
| Voltage | 12 Volts |
| Battery cell composition | Lithium Ion |
| Battery capacity | 2150 Milliamp Hours |
| Compatible vehicle type | Boat, Moto, Passenger Car |
| Automotive fit type | Universal Fit |
| Item dimensions (D x W x H) | 11.7 x 20.8 x 10.7 centimetres |
| Item weight | 1.09 kg |
| Included components | GB40 Jump Starter Power Pack, Heavy Duty Jump Leads, Microfibre Storage Bag, USB-C Charging Cable |
| Number of items | 1 |
| Specification met (as listed) | CE |
| Manufacturer warranty | 1-Year Limited |
| EU spare part availability | 2 Years |
| Best sellers rank | 3 in Car Battery Jump Starters |
| ASIN | B015TKUPIC |
What buyers actually say
Quoted from customer reviews on Amazon
Verified purchaseIt starts engines and it’s handy for camping
“It started my wife’s (1.4L petrol) engine immediately when the car battery went flat, and again the next day, without a recharge in between.”
Verified purchaseWill charge a completely dead battery.
“I am always sceptical of these units and went for a brand that is well known and trusted, and I am glad I did. I have a 2.2l Diesel and it started it first time, so power wise, no issues.”
What it is up against
The rivals it was ranked against in Best Jump Starter 2026: 10 Car Battery Boosters Ranked.
Rank #2
AstroAI B8 Car Jump Starter Power Pack, 7.0L Petrol / 5.5L Diesel, 329g
£31.99
Rank #3
NOCO Boost GB70 2000A UltraSafe Jump Starter Power Pack
£187.98
Rank #4
NOCO Boost X GBX45 1250A Jump Starter, 60W USB-C, 48-Minute Recharge
£118.18
Rank #5
NOCO Boost GB20 500A UltraSafe Jump Starter Power Pack
£71.99
Questions people ask
Will the NOCO Boost GB40 start a diesel?
The listing states it covers petrol engines up to 6.0 litres and diesel engines up to 3.0 litres, from 1000 peak amps. Above 3.0 litres of diesel NOCO points you at a bigger pack in the range, such as the GB70.
How many jump starts do you get per charge?
NOCO states up to 20 starts per charge on engines up to 6.0 litres of petrol. That is the figure on the listing rather than one we measured, and how close you get to it depends on the engine and how flat the battery is.
Can it charge a phone?
The specification table gives the battery as 2,150mAh. A typical phone battery is around 4,000mAh, so treat the power bank function as an emergency top-up rather than a full charge.
What happens if I connect the clamps the wrong way round?
NOCO states the GB40 has spark-proof technology and reverse polarity protection, so a wrong connection does not spark. That is the maker claim; we have not tested it.
What comes in the box?
The listing names the GB40 pack itself, heavy duty jump leads, a microfibre storage bag and a USB-C charging cable.
How heavy is it and will it fit a glovebox?
The specification table gives 1.09 kg and 11.7 x 20.8 x 10.7 centimetres, so it fits most gloveboxes and every boot.
Comments
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