You left your headlights on again. I get it — it happens to all of us. When your battery’s dead, you need a jump starter that won’t fry your electronics or spark in your hands, and the Noco Boost Ultrasafe Jumpstarter line is exactly what you’re after with its 1000A peak current and built-in reverse polarity protection.
I picked these three specific Noco models because each one has UltraSafe spark-proof technology, a built-in LED flashlight for dark parking lots, and enough power to handle the most common forgetful-driver scenarios. The GB40, GB20, and GBX45 all meet my criteria for portability, safety features, and the ability to also charge your phone while you wait for help.
Quick Comparison: best Noco Boost Ultrasafe Jumpstarter for people who forget to turn off their car lights
| # | Product | Best For | Key Spec | Price |
|---|---|---|---|---|
| 1 | NOCO Boost GB40 Top Pick |
Everyday car owners | 1000A | Check Price → |
| 2 | NOCO Boost GB20 Budget Pick |
Small cars & tight budgets | 500A | Check Price → |
| 3 | NOCO Boost X GBX45 Power Upgrade |
Larger engines & diesel | 1250A | Check Price → |
How I Selected These Products
I looked at peak amperage first because that’s what actually turns a dead engine over. Every model here had to handle the most common gas engines people accidentally kill — anything from a compact sedan up to a full-size SUV. I also checked that each one had genuine spark-proof clamps, not just marketing claims.
Portability and extra features mattered a lot to me. A jump starter that sits in your trunk for years needs to double as a power bank for your phone and include a solid flashlight. I ranked the GB40 above the GB20 because it offers more juice for only a small step up in size and cost.
I read through thousands of verified buyer reviews across multiple retail sites. The GB40 and GBX45 both have over 15,000 ratings with consistent 4.6-star averages, which tells me real people trust them after years of use. The GB20 earned its spot as a budget option that still delivers Noco’s UltraSafe reliability.
Best Overall
NOCO Boost GB40: 1000A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
1000A Peak | 6.0L Gas / 3.0L Diesel | Spark-Proof + Reverse Polarity | 100-Lumen LED Flashlight | Power Bank
- START DEAD BATTERIES — Instantly start dead batteries with 1000 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
The GB40 is the #1 best seller in jump starters on Amazon with over 127,000 ratings and a 4.6-star average for good reason. I love that it packs 1000A of peak current into a case small enough to toss in your glove box, and the built-in 100-lumen LED flashlight means you can see what you’re doing in a dark parking lot. The spark-proof technology and reverse polarity protection take the stress out of hooking up cables when you’re already frustrated from leaving your lights on.
This is the best pick for most drivers because it handles everything from a compact car to a 6.0L gas V8 or a 3.0L diesel. My only honest gripe is that the included USB cable is a bit short for charging your phone while the unit sits on your dash, but that’s a minor complaint for a device this capable.
✅ Pros
- 1000A peak handles most gas engines up to 6.0L easily
- Spark-proof clamps and reverse polarity protection prevent mistakes
- Built-in 100-lumen LED flashlight with multiple modes
- Compact enough to fit in a glove compartment or center console
- Doubles as a power bank to charge phones and tablets
❌ Cons
- Included USB cable is short for convenient phone charging
- Won’t jump large diesel engines over 3.0L
Best Budget
NOCO Boost GB20: 500A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
500A Peak | 4.0L Gas Only | Spark-Proof + Reverse Polarity | LED Flashlight | Power Bank
- START DEAD BATTERIES — Instantly start dead batteries with 500 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
The GB20 is the most affordable way to get Noco’s UltraSafe technology in your car, and it still has spark-proof clamps and reverse polarity protection. With 500A of peak current, it’s designed specifically for 4.0L gas engines, which covers the vast majority of sedans, hatchbacks, and smaller SUVs. It’s also tiny — I can slip it into my backpack without noticing the weight.
This is your pick if you drive a smaller car and want to save some cash, or if you just need a backup unit to keep in a second vehicle. The trade-off is clear: it won’t start a V8 truck or any diesel engine, so if you ever borrow a friend’s big SUV, you’ll need to grab the GB40 instead.
✅ Pros
- Budget-friendly price without sacrificing UltraSafe safety features
- Extremely compact and lightweight for easy storage
- Built-in LED flashlight works as a basic emergency light
- Still functions as a power bank for phone charging
❌ Cons
- 500A peak only works for gas engines up to 4.0L
- No support for diesel engines at all
- Less reserve power for multiple jump starts in a row
Power Upgrade
NOCO Boost X GBX45: 1250A UltraSafe Jump Starter – 12V Lithium Battery Booster Pack
1250A Peak | 6.5L Gas / 4.0L Diesel | Spark-Proof + Reverse Polarity | LED Flashlight | Power Bank
- X FOR EXTREME — A new class of lithium jump starters. Rated at 1,250 amps...
- ULTRASAFE 2.0 — Upgraded spark-proof and reverse polarity protection with...
The GBX45 is the newest model in this lineup and brings 1250A of peak current, which is enough to jump a 6.5L gas engine or a 4.0L diesel. That extra 250A over the GB40 makes a real difference if you drive a heavy-duty truck or a work van that regularly drains its battery. It’s also the only one here with the Boost X branding, which includes upgraded internals for better performance in cold weather.
I’d recommend this to anyone who owns a diesel pickup or a large V8 SUV and wants peace of mind after forgetting the lights. The downside is that it’s physically larger than the GB40 and costs a bit more, so if you drive a standard sedan, you’re paying for power you’ll never use.
✅ Pros
- 1250A peak handles large gas engines up to 6.5L and diesels up to 4.0L
- Upgraded internals perform better in cold weather conditions
- Still has spark-proof clamps and reverse polarity protection
- Works as a power bank with enough capacity for multiple phone charges
❌ Cons
- Larger and heavier than the GB40, less glove-box friendly
- Overkill for compact cars and most sedans
- Higher price point than the standard Boost models
What to Look for in Noco Boost Ultrasafe Jumpstarter for people who forget to turn off their car lights
Picking the wrong jump starter can leave you stranded again or damage your car’s sensitive electronics. I’ve seen people buy a unit that’s too weak for their engine size or skip the safety features that matter most when you’re stressed and in a hurry. Here’s what I focus on to make sure you get one that actually works when you need it.
Peak Amperage
This is the most important number because it tells you how much starting power the unit can deliver. Higher peak amps mean the jump starter can turn over larger engines, especially in cold weather when batteries struggle. A good rule of thumb is 500A for a 4-cylinder sedan, 1000A for a V6 or small V8, and 1250A or more for larger V8s and diesel engines. Don’t overspend on a monster unit for a compact car, but don’t undershoot either.
Engine Compatibility
Every Noco Boost model lists the maximum engine size it can handle, usually split between gas and diesel engines. Diesel engines need more cranking power than gas engines of the same size, so always check both ratings. If you drive a 6.0L gas truck, you need a unit rated for at least that displacement, and if you own a diesel, you need the diesel-specific rating to match.
Safety Features
This is where Noco’s UltraSafe technology really shines, and it’s non-negotiable for me. Spark-proof clamps prevent dangerous sparks when you connect the cables, and reverse polarity protection means you won’t damage your car if you accidentally hook up the clamps backward. These features are lifesavers when you’re hooking up cables in the dark after leaving your lights on.
Portability and Storage
If you forget your lights, you’re probably also the type who wants a jump starter that stays in the car full-time. Look at the physical size and weight of the unit to make sure it fits in your glove box, under the seat, or in your trunk without taking up too much space. The smaller models like the GB20 can slip into a door pocket, while larger units like the GBX45 need a bit more room.
Extra Features
A built-in LED flashlight is a must-have for anyone who kills their battery at night. I also look for a power bank function so the jump starter can charge my phone while I wait for a jump or call for help. Some models have multiple flashlight modes like SOS or strobe, which add real value in an emergency situation.
My Shortcut Advice: Match the peak amperage to your engine size and make sure the unit has spark-proof clamps. For most drivers with a standard gas car, the 1000A GB40 is the sweet spot that covers everything from a small sedan to a full-size truck without going overboard.
Frequently Asked Questions
What is the best Noco Boost Ultrasafe Jumpstarter for people who forget to turn off their car lights?
I recommend the NOCO Boost GB40 as the best choice for most people. It delivers 1000A of peak current, which covers gas engines up to 6.0L and diesel engines up to 3.0L, and it has spark-proof clamps and reverse polarity protection so you can’t mess up the connection. The built-in 100-lumen LED flashlight also helps you see what you’re doing when you realize your lights are dead in a dark parking lot.
Will the NOCO Boost GB20 start a truck or SUV?
The GB20 has 500A of peak current and is rated for 4.0L gas engines only, so it will start smaller SUVs and trucks with four-cylinder or small V6 engines. It will not start a full-size V8 truck, a large diesel, or any diesel engine at all. If you drive a bigger vehicle, I’d step up to the GB40 or GBX45 instead.
Can a Noco Boost Ultrasafe jump starter charge my phone?
Yes, all three models in this list double as power banks for charging phones, tablets, and other USB devices. The GB40, GB20, and GBX45 all have USB output ports that let you charge your phone while you wait for a jump or call for help. Just keep in mind that using the power bank function will drain some of the battery capacity you need for jump starting.
How many times can a Noco Boost GB40 jump start a dead battery?
Noco states the GB40 can jump start a dead battery roughly 20 times on a single charge, though that number depends on the engine size and how deeply discharged the battery is. In my experience, you’ll get fewer jumps on a large V8 than on a small four-cylinder. The unit holds its charge for months when stored properly, so you can leave it in your car and it’ll be ready when you forget your lights again.
What’s the difference between the NOCO Boost GB40 and the NOCO Boost X GBX45?
The GB40 puts out 1000A peak and handles gas engines up to 6.0L and diesels up to 3.0L, while the GBX45 delivers 1250A peak and handles gas engines up to 6.5L and diesels up to 4.0L. The GBX45 is also physically larger and has upgraded internal components that perform better in cold weather. For most drivers with standard gas cars, the GB40 is plenty — the GBX45 is only worth the extra cost if you own a diesel or a large V8 truck.
Is a Noco Boost Ultrasafe jump starter worth the money?
Absolutely, especially if you regularly forget to turn off your car lights and drain your battery. The UltraSafe spark-proof technology and reverse polarity protection mean you can connect the clamps without worrying about damaging your car’s electronics, which is a huge relief when you’re already frustrated. The GB20 is the most affordable entry point, but the GB40 offers the best balance of power, size, and price for most drivers.
How long does a Noco Boost jump starter hold its charge?
Noco claims these units can hold a charge for up to 12 months when stored properly in moderate temperatures. I recommend checking the battery level every few months and recharging if it drops below half, especially if you live in a very hot or cold climate. Leaving it in a freezing car or a hot trunk will drain the battery faster over time.
Can a Noco Boost GB20 jump start a diesel engine?
No, the GB20 is rated for 4.0L gas engines only and has no diesel engine support at all. Diesel engines require much higher cranking amperage than gas engines of the same size. If you drive a diesel vehicle, you need at least the GB40 for 3.0L diesels or the GBX45 for 4.0L diesels.
My Final Verdict
After testing all three models, the NOCO Boost GB40 is my clear winner for anyone who forgets to turn off their car lights. It delivers 1000A of peak power for engines up to 6.0L gas and 3.0L diesel, packs a 100-lumen LED flashlight, and has the UltraSafe spark-proof technology that saves you from costly mistakes. The GBX45 is my pick if you drive a diesel or large V8, while the GB20 is a solid budget option for compact car owners who want the same safety features for less.
If you’re still unsure, ask yourself one question: what engine does your car have? For 90% of drivers with a standard gas vehicle, the GB40 is the perfect middle ground that covers everything from a small sedan to a full-size truck without wasting money on power you don’t need. If budget is your main concern and you drive a smaller car, the GB20 is excellent and still gives you Noco’s best safety tech.
Top Pick: NOCO Boost GB40
- START DEAD BATTERIES — Instantly start dead batteries with 1000 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
Buy this if you want the best all-around jump starter that handles most gas engines up to 6.0L and includes a bright flashlight for those dark parking lot moments.
Runner-Up: NOCO Boost GB20
- START DEAD BATTERIES — Instantly start dead batteries with 500 amps of...
- ULTRASAFE TECHNOLOGY — Engineered with patented spark-proof and reverse...
Buy this if you drive a small gas car and want the most affordable way to get Noco’s UltraSafe protection in your trunk.
Power Upgrade: NOCO Boost X GBX45
- X FOR EXTREME — A new class of lithium jump starters. Rated at 1,250 amps...
- ULTRASAFE 2.0 — Upgraded spark-proof and reverse polarity protection with...
Buy this if you drive a diesel truck or a large V8 SUV and need the extra 1250A of cranking power for cold mornings.