Power bank mAh to Wh chart: what is allowed on a plane
As an Amazon Associate, Plainwork Digital earns from qualifying purchases.
Airlines limit watt-hours (Wh), but most power banks are sold by mAh. The conversion is Wh = mAh × volts ÷ 1000. This chart does it for the sizes people actually buy, at the three voltages used on power bank cells, so you can see at a glance which sizes are safe and which sit on the line.
| Capacity | Wh at 3.6 V | Wh at 3.7 V | Wh at 3.85 V | Against the 100 and 160 Wh limits |
|---|---|---|---|---|
| 5,000 mAh | 18 | 18.5 | 19.25 | Under 100 Wh at any voltage |
| 10,000 mAh | 36 | 37 | 38.5 | Under 100 Wh at any voltage |
| 15,000 mAh | 54 | 55.5 | 57.75 | Under 100 Wh at any voltage |
| 20,000 mAh | 72 | 74 | 77 | Under 100 Wh at any voltage |
| 25,000 mAh | 90 | 92.5 | 96.25 | Under 100 Wh at any voltage |
| 26,800 mAh | 96.48 | 99.16 | 103.18 | Depends on the voltage: check the label (near 100 Wh) |
| 27,000 mAh | 97.2 | 99.9 | 103.95 | Depends on the voltage: check the label (near 100 Wh) |
| 30,000 mAh | 108 | 111 | 115.5 | 100 to 160 Wh: airline approval needed |
| 40,000 mAh | 144 | 148 | 154 | 100 to 160 Wh: airline approval needed |
| 50,000 mAh | 180 | 185 | 192.5 | Over 160 Wh: not allowed |
The biggest bank under each limit
- Under 100 Wh: up to 25,974 mAh if the cells are rated 3.85 V, 27,027 mAh at 3.7 V, 27,777 mAh at 3.6 V. If you do not know the voltage, 25,974 mAh is the safe figure.
- Under 160 Wh (the usual maximum on passenger aircraft, and only with airline approval above 100 Wh): up to 41,558 mAh at 3.85 V, 43,243 mAh at 3.7 V.
Why 27,000 mAh is the awkward size
A 27,000 mAh bank is 97.2 Wh at 3.6 V, 99.9 Wh at 3.7 V and 103.95 Wh at 3.85 V. The same label can be fine on one airline and refused on another, because Emirates allows only banks under 100 Wh while the common baseline allows up to 100 Wh without approval. Always look for the Wh printed on the bank. If it says 99.9 Wh or less, you are under the line.
Check the number you are reading
- Rated capacity versus output capacity. Some brands print a second, smaller figure (for example 12,000 mAh at 5 V) for what the bank delivers over USB. Airlines care about the cell capacity at the cell voltage. Use the larger "rated" figure with 3.6 to 3.85 V, or better, the Wh on the label.
- Do not multiply by 5 V. That gives an answer about 35% too high for the cells. The checker rejects voltages above 4.4 V for this reason.
- No Wh and no mAh on the casing? Security can refuse it whatever the maths says.
What next
Type your own numbers into the power bank flight checker to get a verdict for Singapore Airlines, Scoot, Emirates or Lufthansa Group, including how many banks you may carry and whether you can use one in flight. The sources and dates are on the airline rules page. Buying a new one? See how to choose a power bank that is fine in the cabin.
The values above come from the same tested code as the checker (rules checked 2026-10-15); the 3.6 to 3.85 V range covers typical lithium-ion power bank cells, but your bank's label always wins.