Best Jump Starter on Amazon
"Peak amps" — the number every jump starter is sold on — has no governing test standard. No independent body defines the temperature, the load, or the duration, so a $30 unit and a $150 unit can both claim 3,000 peak amps and neither figure is comparable or auditable. The number that is defined is CCA (SAE J537): amps sustained for 30 seconds at 0°F without terminal voltage dropping below 7.2V — and that is precisely the figure this category avoids printing. So buy on disclosure: the Weego 66 (600 CA) and Schumacher SL1397 (500 CA) are among the only units publishing a sustained-current number at all. Want stable chemistry? NOCO Boost Plus GB40 (LiFePO4). Extreme cold or long storage? autowit SuperCap 2.
The two lowest numbers on this page are the two most trustworthy. A unit quoting 600 CA is not weaker than one quoting 4,000 peak amps — it is quoting a different, harder, sustained-load measurement. If a good sustained-current figure existed for the others, it would very likely be on the box. See why don't jump starters disclose CCA? and the Cranking Amp Reality Index.
Four numbers, one real standard
| Term | Standard | Test temperature | Duration |
|---|---|---|---|
| Peak amps | None — no governing test standard | Not defined; manufacturer's choice | Not defined; often a momentary pulse |
| CA (Cranking Amps) | Battery-industry convention | 32°F / 0°C | 30 seconds to a 7.2V floor |
| MCA (Marine Cranking Amps) | Battery-industry convention | 32°F / 0°C | 30 seconds to a 7.2V floor |
| CCA (Cold Cranking Amps) | SAE J537 | 0°F / −18°C | 30 seconds to a 7.2V floor |
CA and MCA use the same 30-second, 7.2V-floor test as CCA but at a milder 32°F, so they read about 20–25% higher than CCA for the identical cell. Full decoder: peak amps vs CA vs CCA vs MCA, is CCA the same as peak amps?, and what do peak amps actually mean?
Who actually publishes a cranking figure
| Unit | Advertised peak | Cranking amps disclosed |
|---|---|---|
| Weego 66 (N66) | 2500A | 600 CA (manufacturer claim, not stated as SAE J537-tested) |
| Schumacher SL1397 | 1000A | 500 CA (manufacturer claim, not stated as SAE J537-tested) |
| Antigravity XP-10 Gen 2 | 3000A | 600A "starting current" (manufacturer term, not a named CA/CCA/MCA standard) |
That is the complete list from our dataset. Every other unit markets peak amps alone. Note that even these disclosed figures are manufacturer cranking-amp claims, not stated SAE J537-certified CCA results — better than nothing, still not lab-audited.
Best disclosure: Weego 66
One of the few jump starters in this category that discloses a separate cranking-amps (CA) figure alongside the peak-amp headline number, instead of marketing peak amps alone.
Best for: Buyers who want at least a partial sustained-current figure to compare against the CCA table. Watch out: The disclosed '600 CA' is not stated as an SAE J537-tested CCA figure — it appears to be a manufacturer cranking-amp claim, not an independently certified cold-cranking-amps rating, so it should still be read as a brand claim rather than a lab-audited standard.
Widely available with a disclosed figure: Schumacher SL1397
A mainstream hardware-store brand that discloses a specific cranking-amps figure (500 CA) on the packaging, not just a peak-amp headline.
Watch out: Battery capacity (mAh/Wh) is not disclosed in the manufacturer's published specs we could find, which is itself the kind of gap our dataset flags as 'not disclosed' rather than guessing a number.
Best chemistry documentation: NOCO Boost Plus GB40
Uses LiFePO4 (lithium iron phosphate) cells, the most thermally stable lithium chemistry in this category, and NOCO discloses the pack's Wh rating plainly.
Watch out: No disclosed cranking-amps (CA/CCA) figure — only the undefined 'peak amps' number is marketed, and our own capacity-based plausibility check flags the 1,000A claim as implausible as a sustained current for this cell size (see the Cranking Amp Reality Index).
LiFePO4 is the most thermally stable lithium chemistry here; standard lithium-ion generally stores more energy for its size, which is why the big-pack units support more jumps per charge. See LiFePO4 vs lithium-ion and how long lithium jump starters last.
Most capacity: HULKMAN Alpha85
Large 74Wh pack gives genuinely high total energy storage and a claimed ~60 jump starts per charge.
Watch out: Marketing labels the 2,000A figure 'peak cranking amp,' blurring peak-amp and cranking-amp language even though no SAE J537 CCA figure is disclosed — read our Peak Amps vs CA vs CCA vs MCA decoder before assuming this is a cranking-amp rating.
Total stored energy (Wh) and cranking current are different questions. A big pack answers "how many times can it jump start a car?" — see how many times can it jump start? — not "can it turn this engine over at 0°F?"
The biggest headline number: GOOLOO GP4000
The highest advertised peak-amp figure in our dataset, paired with a large 24Ah battery for many jump-start cycles per charge.
Watch out: No disclosed cranking-amps (CA/CCA) figure. Our capacity-based plausibility check flags the 4,000A claim as physically implausible even as a brief pulse relative to the pack's stated capacity — see the Cranking Amp Reality Index for the calculation and its assumptions.
Same pattern on the Avapow A28: No disclosed cranking-amps (CA/CCA) figure. The plausibility check in our dataset flags the 3,000A claim as an extreme pulse-only figure relative to the pack's stated capacity — see the derived calculation before comparing it to a CCA-rated product. Both flags are derived estimates with stated assumptions — peak amps divided by rated amp-hours, giving an implied momentary C-rate — not lab measurements, and they do not prove any specific claim is false. What they do show is that a very high implied C-rate is consistent only with an extremely brief pulse, not with the sustained 30-second load CCA measures.
Different chemistry entirely: autowit SuperCap 2
Uses supercapacitors instead of a lithium battery — no cells to age or lose charge capacity over years, and it tolerates extreme temperature ranges (-40C to 70C) that degrade lithium packs.
Watch out: Supercapacitors deliver their charge in seconds and cannot sustain output the way a battery can, so its lowest-in-category 800A peak claim is not directly comparable to lithium units — and it has no mAh/Wh capacity rating at all, since capacitors aren't specified that way.
See lithium vs supercapacitor.
If you drive a diesel
The engine-size line on the box — "up to 8.0L gas / 6.0L diesel" — is a manufacturer recommendation, not an independently verified rating. Diesels draw sustained current through longer glow-plug and compression cycles, which is exactly the behaviour a peak-amp pulse figure does not describe. For a diesel, a disclosed CA or CCA number is worth more than any headline. See best jump starter for diesel trucks, how many amps do I need?, and what the engine-size rating means.
The picks
Research-based picks (how we evaluate), from published manufacturer specifications and stated standards, not hands-on lab tests. Live Amazon search links, no prices or ratings, an honest drawback on each.
Weego 66 (N66)
2,500A advertised peak, 600 CA disclosed, 66Wh lithium-ion, rated for 10L+ gas / 5L+ diesel
One of the few jump starters in this category that discloses a separate cranking-amps (CA) figure alongside the peak-amp headline number, instead of marketing peak amps alone.
Best for: Buyers who want at least a partial sustained-current figure to compare against the CCA table
Watch out: The disclosed '600 CA' is not stated as an SAE J537-tested CCA figure — it appears to be a manufacturer cranking-amp claim, not an independently certified cold-cranking-amps rating, so it should still be read as a brand claim rather than a lab-audited standard.
Check price on AmazonNot deciding today? Add it to your cart over there — Amazon keeps it saved (and flags any price change) until you're ready.
Schumacher SL1397
1,000A advertised peak, 500 CA disclosed, lithium-ion, battery capacity not disclosed
A mainstream hardware-store brand that discloses a specific cranking-amps figure (500 CA) on the packaging, not just a peak-amp headline.
Best for: Buyers who want a widely available big-box unit with at least a partial disclosed cranking spec
Watch out: Battery capacity (mAh/Wh) is not disclosed in the manufacturer's published specs we could find, which is itself the kind of gap our dataset flags as 'not disclosed' rather than guessing a number.
Check price on AmazonNot deciding today? Add it to your cart over there — Amazon keeps it saved (and flags any price change) until you're ready.
NOCO Boost Plus GB40
1,000A advertised peak, 2,150mAh/24Wh LiFePO4, rated for 6.0L gas / 3.0L diesel
Uses LiFePO4 (lithium iron phosphate) cells, the most thermally stable lithium chemistry in this category, and NOCO discloses the pack's Wh rating plainly.
Best for: Buyers who want a well-documented small-engine unit from a brand that publishes real Wh figures
Watch out: No disclosed cranking-amps (CA/CCA) figure — only the undefined 'peak amps' number is marketed, and our own capacity-based plausibility check flags the 1,000A claim as implausible as a sustained current for this cell size (see the Cranking Amp Reality Index).
Check price on AmazonNot deciding today? Add it to your cart over there — Amazon keeps it saved (and flags any price change) until you're ready.
HULKMAN Alpha85
2,000A advertised peak, 20,000mAh/74Wh lithium-ion, rated for 8.5L gas / 6.0L diesel
Large 74Wh pack gives genuinely high total energy storage and a claimed ~60 jump starts per charge.
Best for: Larger gas engines and buyers who want more charge cycles between recharges
Watch out: Marketing labels the 2,000A figure 'peak cranking amp,' blurring peak-amp and cranking-amp language even though no SAE J537 CCA figure is disclosed — read our Peak Amps vs CA vs CCA vs MCA decoder before assuming this is a cranking-amp rating.
Check price on AmazonNot deciding today? Add it to your cart over there — Amazon keeps it saved (and flags any price change) until you're ready.
autowit SuperCap 2
800A advertised peak, supercapacitor (no lithium cells, not rated in mAh), rated up to 8.0 gas / 4.0L diesel
Uses supercapacitors instead of a lithium battery — no cells to age or lose charge capacity over years, and it tolerates extreme temperature ranges (-40C to 70C) that degrade lithium packs.
Best for: Buyers in extreme climates or infrequent users who don't want a lithium pack self-discharging in storage
Watch out: Supercapacitors deliver their charge in seconds and cannot sustain output the way a battery can, so its lowest-in-category 800A peak claim is not directly comparable to lithium units — and it has no mAh/Wh capacity rating at all, since capacitors aren't specified that way.
Check price on AmazonNot deciding today? Add it to your cart over there — Amazon keeps it saved (and flags any price change) until you're ready.
GOOLOO GP4000
4,000A advertised peak, 24,000mAh lithium-ion, rated up to 10.0L gas / 10.0L diesel
The highest advertised peak-amp figure in our dataset, paired with a large 24Ah battery for many jump-start cycles per charge.
Best for: Buyers drawn to the biggest peak-amp headline number who want to understand what it actually means before buying on that number alone
Watch out: No disclosed cranking-amps (CA/CCA) figure. Our capacity-based plausibility check flags the 4,000A claim as physically implausible even as a brief pulse relative to the pack's stated capacity — see the Cranking Amp Reality Index for the calculation and its assumptions.
Check price on AmazonNot deciding today? Add it to your cart over there — Amazon keeps it saved (and flags any price change) until you're ready.
Avapow A28
3,000A advertised peak, 23,800mAh lithium-ion, rated for 8.0L gas / 8.0L diesel
A budget-tier unit with a large 23.8Ah pack and multiple marketed safety protections (reverse-polarity, over-current, over-temperature).
Best for: Budget buyers wanting a large-capacity pack for phone/device charging as well as jump-starting
Watch out: No disclosed cranking-amps (CA/CCA) figure. The plausibility check in our dataset flags the 3,000A claim as an extreme pulse-only figure relative to the pack's stated capacity — see the derived calculation before comparing it to a CCA-rated product.
Check price on AmazonNot deciding today? Add it to your cart over there — Amazon keeps it saved (and flags any price change) until you're ready.
Browse jump starters on Amazon
Which should you buy?
You want a real sustained-current figure: Weego 66, or Schumacher SL1397.
Small engine, best-documented chemistry: NOCO Boost Plus GB40.
Most jumps and device charging per charge: HULKMAN Alpha85.
Extreme cold, or it lives in the boot for a year untouched: autowit SuperCap
2.
Diesel: insist on a disclosed CA or CCA figure.
Never buy on: the peak-amp number alone — it has no standard behind it.
Jump-starting carries procedure and polarity risk. Follow the unit's manual and your vehicle owner's manual for the correct clamp order — see how to jump start a car safely and can a jump starter damage my car? This page is a specification reference, not a substitute for those instructions.
Frequently Asked Questions
On disclosure — which is the only basis available in this category — the Weego 66 and the Schumacher SL1397, because they are among the very few units that publish a cranking-amps figure (600 CA and 500 CA respectively) alongside the peak-amp headline instead of marketing peak amps alone. The NOCO Boost Plus GB40 is the pick if you want certified-stable LiFePO4 chemistry and a plainly stated Wh rating. For extreme cold or long storage, the autowit SuperCap 2 uses supercapacitors with no lithium cells to age.
Less than the size of the number suggests, because peak amps has no governing test standard. No independent body defines the temperature, the load, or the duration behind it — manufacturers set their own test conditions or disclose none at all. A 30-dollar unit and a 150-dollar unit can both claim 3,000 peak amps, and neither figure is directly comparable to the other or auditable by a third party. It is often a momentary pulse lasting fractions of a second.
No, and the difference is the whole point. Cold Cranking Amps is defined by SAE J537: the current a battery sustains for 30 seconds at 0°F without terminal voltage falling below 7.2V on a 12V battery. It is the one cranking-related figure in this category with a real, citable engineering standard behind it — which is exactly why most jump-starter marketing avoids it in favour of an undefined peak-amp number. A 30-second sustained load and an instantaneous pulse are not the same measurement.
CA and MCA use the same 30-second, 7.2V-floor test as CCA but at a milder 32°F rather than 0°F. Because of that easier temperature, CA and MCA figures read roughly 20 to 25 percent higher than CCA would for the identical cell. All three are sustained-current measurements, which makes them meaningfully different from an undefined peak-amps claim — but they are not interchangeable with each other either, so check which one a listing is quoting.
Across the current lineup, a disclosed cranking-amps figure is the exception rather than the rule; most listings market only the undefined peak-amp number. That pattern of non-disclosure is itself a finding: if a sustained-current figure existed and looked good, it would very likely be on the box. It is why, on this page, the two units quoting the lowest cranking numbers are treated as the most informative rather than the weakest.
The engine-displacement guidance printed on the packaging — for example "up to 8.0L gas / 6.0L diesel" — is a manufacturer recommendation, not an independently verified rating. Diesel engines in particular draw sustained current through longer glow-plug and compression cycles, which is one more reason a disclosed CCA or CA figure matters far more to a diesel owner than a peak-amp headline. Where a sustained figure is available, use it; where only peak amps is offered, treat the engine rating as a claim.
LiFePO4 — lithium iron phosphate — is the most thermally stable lithium chemistry in this category, which is the main argument for it. Standard lithium-ion packs tend to offer more total stored energy for their size, so they support more jump-starts and more device charging per charge. Neither chemistry changes the underlying disclosure problem: a LiFePO4 unit marketing only peak amps tells you no more about sustained cranking current than a lithium-ion one does.
Jump-starting carries both procedure and polarity risk: connecting cables in the wrong order or the wrong polarity can cause sparks, arcing, or damage to a vehicle's electronics. The usual clamp order is positive to positive first, then negative to a grounded metal point on the vehicle rather than the dead battery's negative terminal. Always follow the jump starter's own manual and your vehicle owner's manual — this page is a specification reference, not a substitute for those instructions.