Best jump starters 2025: tested, reviewed and rated

There’s little more irritating than trying to start a car and hearing a groaning attempt from the starter motor, or the tell-tale clicking that usually signifies a dead battery. Inevitably, it only ever happens when you need to be somewhere urgent, it’s dark or it’s cold. Or normally, all three. 

In the past this would mean finding a set of jump leads and a helper to place a running car nose-to-nose, then connecting the leads to give your car’s battery enough boost to start the car. Any one of those elements may be tricky, if not impossible.

Now, battery jump packs are available to boost ailing electrics enough to start the engine – and hopefully put enough charge back into the battery to continue your journey to recharge the vehicle battery or source a replacement. 

Read more: Best car battery chargers

Today, small, glovebox-sized jump starters pack a real punch and have replaced older, larger items. Some also offer a range of other benefits, such as a torch or USB sockets to charge a phone.

To find the best jump starters you can currently buy, we selected five of the biggest names on the market to see which is worth your money. 

- Best overall jump starter – Clarke JumpStart Micro 1200

- Best jump starter for performance – Ring UltraBoost 1500

- Best value jump starter – Sealey RS800

The products or services referenced in this story have been reviewed independently by our experts. When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network. However, this will never influence our opinion or ratings.

Best jump starters 2024

Clarke JSM1200 – Best overall jump starter

What Car? Rating 5/5

Pros
- Excellent starting performance
- Good range of features
- LED status display

Cons
- Completely dead when battery exhausted
- Overheat warning after every start
- Limited availability

The Clarke has an air of quality and industrial-bias in its design. Despite looking like painted aluminium, the unit’s case is made from plastic with fins on the side and textured patterns top and bottom. It has a small LED display showing the battery charge state and other information and a pair of USB outputs rated at 3.0A and 2.1A, plus a 12-volt pin socket. It charges through a USB-C lead, either from home or via a car’s cigarette lighter; both the lead and plug adaptor are supplied.

The connection lead and clamps are good quality; the latter are a good size and are as easy to use as the others here. The unit has two LEDs on the side; the green LED illuminates when the charger is ready to go; a red LED and buzzer alerts you to a range of error messages. Helpfully, a list of possible errors is printed on the back of the flying lead allowing you to identify and solve any faults.

Our first test was to start the car using the Clarke alone (the battery was disconnected, leaving the jump starter as the sole source of power). It started the engine without issue, and didn’t sound any different from using a fully-charged vehicle battery. With the vehicle battery reconnected and the Clarke mated to the under-bonnet terminals, it started the engine 21 times – the greatest number of assisted starts of any of the units on test here. By the end, the display showed 7% but the unit shut itself down and wouldn’t power-up the display. 

Oddly, after each successful engine start, the unit would beep and the red LED would come on solidly, indicating it was overheating. Removing the smart cable and plugging it back in immediately stopped the beeping and the LED illumination. 

Tester’s insight

“On first impressions, plastic made to look like metal feels a little incongruous but once I started to use it, it became clear that the Clarke is an impressive bit of kit. Notwithstanding some confusion over the size of the internal battery (the included documentation states a 7.2Ah battery but the Clarke and Machine Mart websites say 12Ah), it was the best performer here, suggesting the latter. It recorded the greatest number of successful starts and has an impressive feature list. A great all-round performer and a decent bargain too.”

Buy it if
- You want the best combination of performance and value
- You want useful additional features

Don’t buy it if
- You have an aversion to plastic masquerading as metal
- You want a tailored, foam-cut storage case

The facts

Ring UltraBoost 1500 – Best jump starter for performance

What Car? Rating - 5/5

Pros
- Display shows battery status
- Quality feel to construction and use
- High peak-current output

Cons
- Only one USB output
- More expensive than competitor
- The largest here when connected

The Ring UltraBoost 1500 feels like a quality product, comprising what appears to be two distinct sections because the battery pack is separate to the battery clamp module. 

The main battery pack consists of a display showing the battery status, plus an LED flashlight and the electrical outputs which comprise the battery clamp connector, a USB-C input/output and a USB-A output. The battery-clamp block fits to the battery pack snugly and positively and has a design preventing the two being connected incorrectly. The clamps feel robust and with a good amount of clamping force. It comes with a USB-C to USB-C and a USB-C to USB-A which can charge other devices as well as the main battery. 

In use, the Ring started the vehicle’s engine with the main battery disconnected easily, sounding as if the main battery was in full health. It connected easily and securely to the under-bonnet jump terminals and automatically set itself to output when the vehicle battery was detected. The main display showed the decreasing amount of charge in the unit with the green LED indicator for connections and operation eventually turning red to show insufficient energy for further starts. In the end, it stopped supplying power at an indicated 14% after 20 successful engine starts. 

Tester’s insight

“The Ring is a really nice unit with a quality feel. It states 1500A of peak output, which is impressive for a relatively small battery, and the second-highest number of start episodes is impressive. The Ring offers the best performance, but lacks the all-round brilliance of the test-winning Clarke.”

Buy it if
- You want a great combination of performance, price and quality
- You want the easiest to use

Don’t buy it if

- You want the cheapest
- You want the smallest ready-to-go unit

The facts

Noco Boost XL 1500A – Best jump starter for quality

What Car? Rating - 4/5

Pros
- Great quality
- Strong terminal clamping force
- High peak-current output

Cons
- Clamps may be too large or stiff for some
- Performance adequate at best
- Expensive

The Noco Boost XL 1500A is a serious bit of kit; the heaviest here despite what is potentially the smallest-capacity battery. We say potentially, because without knowing the voltage of the internal battery it’s impossible to say for sure. The case seems to pack a lot of electronics, with status LEDs, operating and twin-LED-flashlight switches and a manual override. It’s large and has a solid, weighty and quality feel to it, as you’d hope for the hefty price, but it does come with a USB/microUSB charging lead, a 12-volt power-socket converter and a carry pouch. In addition to the connector for the battery clamps, it has a single USB output rated at 2.1A.

The sprung-loaded battery clamps are well made, although they need a tight squeeze to release them from the plastic block they are supplied fitted to, which is designed to prevent them from shorting-out the unit. In fact, they may well be too stiff for some – we measured almost 10kg of force to open either one. The connector plug for the clamps joins to the main power pack solidly, with a rubber cover protecting the socket when not in use. 

The battery clamps have a wide opening ensuring a strong and secure connection to the vehicle – either the battery terminals or the under-bonnet jump-start options. With the boost function activated, the pack started the vehicle with the main battery bypassed although the car did feel fractionally slower to turn over than when it was connected to the battery. With the battery reconnected, it then went on to start the engine 15 times before it was exhausted. The four coloured LEDs gave an indication of the state of charge but it seemed a little optimistic, showing two LEDs with just two starts left. 

Tester’s insight

“The Noco feels like it means business – it’s weighty, has a quality case and vehicle connectors and that override means it will start even the flattest of batteries. However, while its quality is impressive, the clamps are stiff and not easy to open to get a decent grasp of the battery terminals. The Noco also recorded the second-lowest number of starts (15), which was slightly disappointing. It’s expensive, too.”

Buy it if
- You want the best connection to the flat vehicle
- You want the best build quality

Don’t buy it if
- You're on a budget
- You want the ultimate number of starts

The facts

Sealey RoadStart 800 – Best jump starter for value

What Car? Rating - 4/5

Pros

- Nicely-made unit
- Decent performance
- Force-start function

Cons

- Annoying power-port cover
- Battery status LEDs inconsistent
- Flashlight not as bright as some

The Sealey RoadStart 800 is a fairly unassuming unit, with a plastic-clad battery pack and plug-in battery terminal clamps, plus a force-start function switch on the module. This has a red/green LED to indicate whether or not the battery is connected correctly and if the charger’s temperature is too high, or its voltage too low. It also houses the force-start button that will bypass battery sensing to ensure the full output is available to start the car.

The main unit has a switch to illuminate the four status LEDs which indicate the unit’s charge, and to activate the three-function LED flashlight. The electrical connections are hidden behind a protective rubber flap which can be very tricky to remove, but include connectors for the battery-clamp unit, a microUSB input for charging, and a USB output for charging other devices. 

When testing, the Sealey just about started our Volvo’s engine with the host battery disconnected and felt slower to turn the starter motor than some others here. With the vehicle’s battery reconnected and the Sealey unit clamped to the car’s jump terminals – a simple process because the clamps were small enough to easily compress – the start process was simple. The LED flashed red and green to indicate it was ready for use, and it started the engine 19 times before the LED flashed green to indicate the unit was exhausted. By this point, the four small status LEDs on the main unit had been flashing for around three attempts. 

Tester’s insight

“The Sealey gave an impressive performance from a fairly small and unobtrusive battery pack. The flashing LED was useful to show that it was correctly connected, but the status LEDs on the main unit were slightly optimistic, since they flashed to suggest the starter was depleted with at least two further starts left in reserve.”

Buy it if

- You’re on a budget
- You want easy plug and play

Don’t buy it if

- You want accurate information on battery status
- You want a super-bright flashlight

The facts

Laser 7405 – Best jump starter for features

What Car? Rating - 3/5

Pros
- High-quality build
- Good range of features
- Solid on/off switch

Cons

- Small internal battery
- Shortest longevity here
- Expensive

The Laser 7405 is a compact unit housed in a hard plastic case with a connection module that includes an LED display highlighting a variety of information. It has a host of features, including a USB-C input for charging and two USB outputs, one rated at 3.0A and one at 2.1A for charging external devices. It’s supplied with a charge/output lead with Lightning, USB-C and microUSB plugs so it can charge a range of external devices. 

The side-mounted on/off switch on the side is hard to inadvertently operate and trigger short-circuits. There’s a display on the connection module which shows a variety of information, including its own battery voltage – which is also indicated by four LEDs on the front of the unit. It also shows the target battery voltage and various warnings, including reverse polarity and overheating. 

In use, the battery clamps are fairly small but large enough to grip the car’s battery terminals or under-bonnet jump-start connectors. They’re stiff enough for good contact yet usable. The connection module joins to the battery pack easily; switch the unit on and the LEDs lights activate.

Even though the Laser doesn’t have a force-start function, it still turned the engine over in our tests, although not fast enough to start it when the main vehicle battery was disconnected. With the battery connected and the jump starter’s clamps on the under-bonnet terminals, it started the engine 13 times before finally exhausting itself, accompanied by a beeping from the connector module. 

Tester’s insight

“I’ve tried many Laser products over the years and their quality and performance have always impressed me. This is another quality item from the manufacturer’s range but it’s expensive which, combined with the fact it has the smallest battery here (notwithstanding an unknown directly-comparable capacity for the Noco) it ran out of steam the soonest. However, 13 starts is still a performance that would suit many users in the real world.”

Buy it if
- You don’t need ultimate performance
- You want reassurance of total shutdown

Don’t buy it if
- You want the biggest internal battery possible
- You’re on a budget

The facts

How to choose a jump pack

The most important choice to make is to decide the current-capacity you need. Most jump-starter packs will give you a guide by illustrating the size of petrol or diesel engine they are rated for. Typically a jump starter will handle petrol engines of a larger-capacity than diesel because the latter require more power from the battery to get going. It’s important, therefore, to select a jump starter based on the largest engine you’re likely to use it on. 

This will show the jump starter’s current capacity, in terms of its Cold Cranking Amps (CCA) rating. This is the current drawn by the starter motor in cold weather conditions, which represent the toughest test of a battery, and while batteries tend to fail in winter months. This is particularly true for diesel engines.

Don't worry about using a jump starter that is rated higher than the engine you are starting. The engine’s starter motor will only draw the current it needs rather than the jump starter supplying too much current. The jump starter’s current rating indicates what it is capable of supplying if that demand is placed on it, not what it will supply every time it is used. So a higher-rated jump starter won't damage a smaller engine. 

Another function worth looking for, particularly if you want complete reassurance, is some form of override, because some jump starters may not operate if the voltage of the main battery is too low, and may not even register that they’re connected to a battery. An override function allows the jump starter to supply energy to the vehicle battery even if it doesn’t recognise there is a battery there, getting you out of even the deepest trouble. 

Having selected the size of jump starter you require, choice then comes down to extras. Once you know it will help boost your ailing battery, consider whether you want multiple USB outputs to power mobile devices such as phones or tablets or a built-in flashlight for help during darkness. 

How to use a jump pack

In principle, a jump starter simply removes the need for another car to be used to get yours going. Typically, you assemble the jump starter (if required) and connect the clamps to the car battery as you would with a pair of jump leads – black to your battery’s negative terminal and red to its positive. 

For some vehicles, such as the Volvo XC90 we used for this test, the battery itself is located underneath the boot floor. However, there is an additional positive terminal in the engine onto which you’ll connect the red clamp. The black clamp goes to an earthing point alongside to complete the electrical circuit. 

Once both clamps are connected, you switch the jump starter on and start the car as normal. Once the car is running, switch the jump starter off, so the connectors are no longer live, remove them and, if necessary, plug it in to charge while you drive so it’s ready for next time. 

How we test jump packs

We began by specifying the vehicle we would use to test the jump packs, and asked each manufacturer or distributor to provide the most appropriate unit for that vehicle, a diesel-powered, 2010 Volvo XC90 D5 with a 2.5-litre diesel engine.

A failed battery was installed into the car, and we established that with a voltage of 12.3-volts, it was insufficient to start the car. Indeed, it would make the starter-motor solenoid click once before nothing further happened – perfect for our testing. 

Our first test was to attempt to start the engine using the jump pack alone, connected to the battery’s earth cable and directly to the positive cable, which had been disconnected from the battery, so the jump starter was the only source of electrical power for the whole vehicle. This simulated a completely flat battery and required the use of either the stated override or forced-start function, or would show whether the jump packs without this function would be able to supply sufficient power directly to the engine. 

Once this was established, we reconnected the vehicle’s discharged battery and verified that it was still unable to start the engine. Each jump pack in turn was connected to the earth and positive jumping connection under the Volvo’s bonnet and used to start the engine. Each jump pack was used once and then we moved on to the next, rotating them in the same order to allow each to cool between jump-starts. The same connection point was used for each attempt to start. This cycle continued until each jump pack was exhausted and would no longer assist the battery to start the engine. 

While this does not simulate the most extreme demands on a jump pack – cold weather with use of glow plugs then turning over a cold engine full of cold and hence high-viscosity oil – it is a robust comparison of the longevity of each of the units. 

How we rate jump packs

We looked at several factors when assessing and rating the jump packs. 

Performance: How many times can each jump pack assist the main battery to start the engine? Arguably this should only need to be once or twice (by which point, you’ll likely have replaced the vehicle battery) but this is a measure of the relative power and energy of each product. Will it start the engine with the vehicle battery disconnected, simulating a completely dead battery? 

Ease of use: How easy is it to prepare each for use – plugging in the vehicle connectors, for example? Do you need to manually activate the unit or will it automatically be ready for use? How large is the complete package when stored in the provided bag or case? 

Quality: A subjective rating of the perceived quality of each product. We looked at the build of the main units and the connectors to the vehicle battery, the charging leads and the case.

Value for money: We costed the price of each engine start in our test against the price of the unit as per its recommended retail price, as an indication of the value proposition of each product. Note that most of the units are available at prices much lower than the manufacturer’s stated RRP.

The products or services referenced in this story have been reviewed independently by our experts. When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network. However, this will never influence our opinion or ratings.

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