Manufacturers rate battery life, runtime and output under conditions you will never reproduce. We track every case where independent testing measured something different from the box. Some claims collapse. A few are genuinely conservative. Every figure below links to the full review it came from.
Ranked by how far the measured figure lands below the rating.
| Product | Claimed | Measured | Gap |
|---|---|---|---|
| Goal Zero Nomad 20 Solar output | 20 W | 8 W | −60% |
| Anker Solix PS30 Solar output | 30 W | 14 W | −53% |
| Dyson V15 Detect Runtime | 60 min | 20–40 min | −50% |
| JBL Charge 6 Battery | 24 h | ~13 h | −46% |
| Levoit LVAC-200 Runtime | 50 min | 30 min | −40% |
| Bose SoundLink Flex (2nd Gen) Battery | 12 h | ~7–10 h | −29% |
| BigBlue 28W Solar output | 28 W | 20 W | −29% |
| JBL Flip 7 Battery | 16 h | ~10–13 h | −28% |
| DJI Mini 5 Pro Flight time | 36 min | 27–33 min | −17% |
| FlexSolar 40W Solar output | 40 W | 35 W | −13% |
| Fitbit Charge 6 Battery — rating assumes always-on display off | 5–7 days | ~3 days | setting-dependent |
| DJI Mini 5 Pro Weight — the 250 g regulatory line | 249.9 g | 252–253 g | over the limit |
Credit where it is due — these were measured better than advertised.
| Product | Claimed | Measured | Gap |
|---|---|---|---|
| Anker Soundcore Motion 300 Battery | 13 h | ~16 h | +23% |
| Anker Soundcore Q45 Battery, ANC on | official spec | ~56 h | beats spec |
| Sony WH-CH720N Battery, ANC on | official spec | 40+ h | beats spec |
| Turtle Beach Stealth 600 Gen 3 Battery | 80 h | 83 h 42 m | +5% |
We don't run our own lab, and we say so. Every measured figure here is drawn from published independent testing or verified owner reports, and is cited in the full review linked on each row. Where a source reported a range, we show the range rather than the flattering end of it.
A gap is not automatically a scandal. Battery ratings are measured at fixed volume or with features disabled, and solar output is rated at panel-face irradiance you will not see on a cloudy afternoon. The point isn't that manufacturers lie — it's that the rated number and the number you'll live with are different, and only one of them is printed on the box.
Found a figure we got wrong, or newer testing that supersedes ours? That's a correction we want — our scores move when the evidence does.