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The Cranking Amp Reality Index

Jump starters are marketed almost entirely on "peak amps" — a figure with no governing test standard. This dataset lines up the current portable-jump-starter lineup by what's actually disclosed: advertised peak amps, any published cranking-amps figure, battery capacity and chemistry, engine-size guidance, and a clearly-labeled derived plausibility flag comparing the peak-amp claim to the battery's stated capacity. No specific product's claim is asserted to be false — the numbers are presented side by side, and the absence of a governing standard speaks for itself.

The one thing to know: Across the current jump-starter lineup, disclosed cranking-amps (CA/CCA) figures are the exception, not 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 likely be on the box.

License & how to cite

License: CC BY 4.0 — free to use with attribution.

How to cite: Jump Starter Decoded, "The Cranking Amp Reality Index," version 1.0, July 30, 2026. https://jumpstarter-decoded.pages.dev/cranking-amp-reality-index/

The dataset

BrandModelPeak amps (advertised)Cranking amps (disclosed)Battery capacityChemistryEngine guidanceImplied C-ratePlausibility flag
NOCO Boost Plus GB40 1000 not disclosed 2150 mAh / 24 Wh LiFePO4 up to 6.0L gas / 3.0L diesel ~465C implausible as sustained (extreme pulse-only)
HULKMAN Alpha85 2000 not disclosed (marketed as "peak cranking amp") 20000 mAh / 74 Wh Li-ion up to 8.5L gas / 6.0L diesel ~100C extreme pulse-only (borderline)
Weego 66 (N66) 2500 600 CA (manufacturer claim, not stated as SAE J537-tested) 66 Wh (~5500 mAh implied at 12V) Li-ion 10L+ gas / 5L+ diesel ~455C implausible as sustained (extreme pulse-only)
GOOLOO GP4000 4000 not disclosed 24000 mAh Li-ion up to 10.0L gas / 10.0L diesel ~167C implausible as sustained (extreme pulse-only)
Schumacher SL1397 1000 500 CA (manufacturer claim, not stated as SAE J537-tested) not disclosed Li-ion not specified in published spec sheet not calculable (capacity not disclosed) not calculable (capacity not disclosed)
Antigravity XP-10 Gen 2 3000 600A "starting current" (manufacturer term, not a named CA/CCA/MCA standard) 16000 mAh Li-ion up to 7.3L diesel ~188C implausible as sustained (extreme pulse-only)
Avapow A28 3000 not disclosed 23800 mAh Li-ion up to 8.0L gas / 8.0L diesel ~126C extreme pulse-only
autowit SuperCap 2 800 not disclosed N/A — supercapacitor, not rated in mAh/Wh Supercapacitor up to 8.0L gas / 4.0L diesel not applicable (capacitor chemistry) not applicable (capacitor chemistry)
DBPOWER G16 3000 not disclosed 80.66 Wh (~6720 mAh implied at 12V) Li-ion up to 10.0L gas / 8.0L diesel ~446C implausible as sustained (extreme pulse-only)

How the plausibility flag is calculated (assumptions stated plainly)

A plausibility flag compares a unit's advertised peak-amp claim to its disclosed battery capacity using a simple, stated assumption (peak amps ÷ rated amp-hours = an implied momentary C-rate). This is a derived estimate with named assumptions, not a lab measurement — it does not prove any specific product's claim is false, but very high implied C-rates are consistent only with an extremely brief instantaneous pulse, not a sustained 30-second cranking load like the one CCA actually measures.

The math: we divide the advertised peak-amp figure by the disclosed battery capacity in amp-hours (mAh ÷ 1000, or Wh ÷ 12V where only Wh is published) to get an implied momentary C-rate. We then bucket the result: under ~50C is labeled "high but plausible for a brief high-drain pulse," ~50–150C is labeled "extreme pulse-only (borderline)," and over ~150C is labeled "implausible as sustained (extreme pulse-only)." This is a derived estimate with a stated assumption, not a lab measurement, and it says nothing about whether a unit will successfully start a given engine.

Why so many rows say "not disclosed"

Across the current jump-starter lineup, disclosed cranking-amps (CA/CCA) figures are the exception, not 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 likely be on the box. See the full standards breakdown at Peak Amps vs CA vs CCA vs MCA.

Caveats — read before citing a row

Methodology & versioning

Version 1.0 — published July 30, 2026. Facts are drawn from manufacturer specification pages and public retailer listings (Amazon, Walmart, eBay, brand sites), cross-checked against SAE's public J537 summary and Battery Council International's CA/MCA conventions. We do not test jump starters ourselves; this is a specifications-and-disclosure reference, not a lab result. Corrections: if a manufacturer updates a spec sheet or we find an error, this page and the CSV below are updated in place and the version/date bumped — see How We Evaluate for our full editorial policy.

Machine-readable download: the full table is available as CSV at /cranking-amp-reality-index.csv (version-pinned copy: /cranking-amp-reality-index-v1.0.csv), and a condensed digest is maintained in /llms-full.txt.

This page is a specifications and disclosure reference, not a safety or performance guarantee for any vehicle or product.

Frequently Asked Questions

A normalized dataset that lines up the current lineup of portable lithium jump starters by what each manufacturer actually discloses: advertised peak amps, any disclosed cranking-amps figure, battery capacity and chemistry, engine-size guidance, and a derived plausibility flag comparing the peak-amp claim to the battery's stated capacity. It exists because no neutral third-party reference for this comparison existed before it.

No. The flag is a derived estimate built from a stated assumption (advertised peak amps divided by the disclosed amp-hour capacity, giving an implied momentary C-rate). It does not measure anything in a lab and does not accuse any specific product of lying — it flags when a claim is consistent only with an extremely brief instantaneous pulse rather than a sustained current, and lets you weigh that alongside the marketing.

Because that's what the manufacturers' own published specs show. Most jump-starter listings market only an undefined peak-amp figure and do not publish a cranking-amps (CA) or Cold Cranking Amps (CCA) rating at all. We record that gap with a clean, uniform 'not disclosed' token rather than guessing a number — the pattern of non-disclosure is itself one of the dataset's findings.

No. SAE J537 is a defined, audited engineering standard for Cold Cranking Amps. Almost none of the products in this dataset publish an SAE J537-tested CCA figure; where a brand discloses something called 'cranking amps' or 'starting current,' we say so explicitly and note that it is a manufacturer claim, not a certified CCA rating, unless stated otherwise.

Yes. It's released under a CC BY 4.0 license — free to use with attribution. See the how-to-cite block below.