Jump Starters, Decoded by the Standard That Actually Exists
Every portable jump starter is marketed on "peak amps" — a figure with no governing test standard, no defined duration, and no defined load. The one number with a real engineering standard behind it is Cold Cranking Amps (CCA), defined by SAE J537 as the current a battery sustains for 30 seconds at 0°F without its terminal voltage dropping below 7.2V. Almost no jump starter discloses it. We built the Cranking Amp Reality Index to show, side by side, what's disclosed, what isn't, and whether an advertised peak-amp claim is even plausible given the battery behind it.
Search "best jump starter" and every result is published by a brand selling its own jump starters — Wolfbox, Hulkman, Weego — telling you their peak-amp number is the one that matters. We start somewhere else: the contaminant here isn't a chemical, it's an undefined marketing figure, and the closest thing to a neutral, third-party reference for how to actually read the spec sheet did not exist before this site.
Start with the two reference pages
The one thing to know: "Peak amps" has no governing test standard. No independent body defines the temperature, the load, or the duration behind the number — manufacturers set their own test conditions, or disclose none at all. A $30 unit and a $150 unit can both claim "3000 peak amps," and neither figure is directly comparable to the other or auditable by a third party.
How we work
We're a research-based reference site: we analyze manufacturer specification sheets, SAE and battery-industry standard definitions, and public retailer listings rather than physically testing units. We never claim a specific product's advertised figure is false — we present disclosed numbers side by side and let the absence of a governing standard for "peak amps" speak for itself. Read our full methodology →