27,000 mAh in watt-hours (Wh)
27,000 mAh is 97.2–103.95 Wh at rated voltages of 3.6–3.85 V. Battery rules for flights use watt-hours (Wh), not milliamp-hours (mAh), and the Wh value depends on the rated voltage printed on the battery. We do not assume a voltage for you: find yours on the label and read that row.
The table shows which FAA carry-on rule for power banks covers each Wh value (reviewed 2026-10-27), and how each airline's own reviewed Wh limit treats it. You need to meet both: an FAA line alone is not a yes. TSA screening applies as well.
The FAA power bank rules are being rechecked against their official source, so this page shows the Wh values only for now.
Wh = mAh × rated voltage (V) ÷ 1,000
| If the label says | Watt-hours | FAA carry-on rule for that Wh | Airlines' own rules for that Wh |
|---|---|---|---|
| 3.6 V | 97.2 Wh27,000 × 3.6 ÷ 1,000 | FAA: allowed in carry-on Power bank rated up to 100 Wh: allowed in carry-on baggage. Being rechecked | Within their 100 Wh limit; their other conditions apply: American Airlines, JetBlue Airways, Delta Air Lines, Breeze Airways, Southwest AirlinesBeing rechecked: American Airlines, JetBlue Airways, Delta Air Lines, Breeze Airways, Southwest Airlines Not confirmed (no reviewed rule we can apply to this Wh value): Alaska Airlines, Frontier Airlines, Allegiant Air, United AirlinesBeing rechecked: Alaska Airlines, Frontier Airlines, Allegiant Air, United Airlines |
| 3.7 V | 99.9 Wh27,000 × 3.7 ÷ 1,000 | FAA: allowed in carry-on Power bank rated up to 100 Wh: allowed in carry-on baggage. Being rechecked | Within their 100 Wh limit; their other conditions apply: American Airlines, JetBlue Airways, Delta Air Lines, Breeze Airways, Southwest AirlinesBeing rechecked: American Airlines, JetBlue Airways, Delta Air Lines, Breeze Airways, Southwest Airlines Not confirmed (no reviewed rule we can apply to this Wh value): Alaska Airlines, Frontier Airlines, Allegiant Air, United AirlinesBeing rechecked: Alaska Airlines, Frontier Airlines, Allegiant Air, United Airlines |
| 3.85 V | 103.95 Wh27,000 × 3.85 ÷ 1,000 | FAA: airline approval needed Power bank rated 101-160 Wh: carry-on only, with airline approval, up to two per person. Being rechecked | Not allowed (over their 100 Wh limit): American Airlines, JetBlue Airways, Delta Air Lines, Breeze Airways, Southwest AirlinesBeing rechecked: American Airlines, JetBlue Airways, Delta Air Lines, Breeze Airways, Southwest Airlines Not confirmed (no reviewed rule we can apply to this Wh value): Alaska Airlines, Frontier Airlines, Allegiant Air, United AirlinesBeing rechecked: Alaska Airlines, Frontier Airlines, Allegiant Air, United Airlines The FAA rule asks for airline approval at this Wh value, but the reviewed rules of American Airlines, JetBlue Airways, Delta Air Lines, Breeze Airways and Southwest Airlines allow power banks up to 100 Wh only, and we hold no reviewed rule under which they approve a larger one. |
Work out the Wh of your own battery
These voltages are examples, not an assumption about your battery. If your battery shows a different rated voltage, the Wh value is different too.
Checked bags, under the FAA rule: Power bank: not allowed in checked baggage.
Source: FAA: Airline Passengers and Batteries. Reviewed 2026-10-27.
Check the label on your battery
- If the label prints a Wh value, use that number. You do not need to calculate anything.
- If it prints only mAh, look for the rated (nominal) voltage on the same label and use the row above for that voltage, or enter both values in the calculator.
- If you cannot find the rated voltage, do not guess one. The Wh calculator gives no result without it.
Is a 27,000 mAh power bank allowed on a plane?
It depends on the Wh rating of your own power bank, and so on its rated voltage. The table above shows where each example voltage puts it. A rule from security screening, from the dangerous goods regulations and from your airline can all apply at once, and you need to meet every one of them. Enter the values printed on your battery in the Wh calculator to see the reviewed rules for that Wh value. Nothing you enter leaves your browser.
Power bank rules by airline
Airlines set their own power bank limits on top of the FAA rule, and the stricter one decides. The reviewed rules for each airline, with how many you may carry and where to keep them: