Power Bank Flight Carry-On Calculator (Korea)

Whether a power bank may fly with you is decided in watt-hours (Wh), yet most products print only mAh in large type. This calculator takes the capacity in mAh and the rated voltage, converts them to watt-hours, and tells you which band the result falls in: allowed without approval, allowed only with the airline's approval, or not allowed at all. Enter how many you plan to take and it also shows whether you hit the limit of 2 per person.

The verdict follows the rule Korea's Ministry of Land, Infrastructure and Transport announced on 8 April 2026 and applied from 20 April 2026. Up to 100Wh needs no approval, over 100Wh and up to 160Wh needs the airline's approval, the two bands together are capped at 2 per person, and anything over 160Wh cannot be carried. If the product shows a Wh figure you can enter it directly, and the mAh and voltage fields disappear.

Use it while packing for a trip, when you wonder whether a particular power bank can come along. It helps people who own or plan to buy a large-capacity unit, and families working out how many each person can carry. Before this rule (from 1 March 2025) Korea allowed up to 5 power banks of 100Wh or less per person, so anyone packing three or four from memory will have to leave some at the airport.

It is also useful before buying one. Check first whether the capacity you have in mind sits in the no-approval band and you will not need to seek airline approval. Airlines and countries may be stricter, though. The ministry named Hong Kong, Singapore and Japan as examples and told travellers to confirm the carry-on rules with their airline before departure. The verdict here reflects the Korean ministry's rule. If your airline's guidance is stricter, follow the airline.

Watt-hours are capacity in mAh multiplied by rated voltage and divided by 1000. 국토교통부 보도자료 equates 100Wh with 27,000mAh and 160Wh with 43,000mAh. Since 27,000mAh × 3.7V ÷ 1000 = 99.9Wh, that conversion assumes a rated voltage of 3.7V. That is why the voltage field defaults to 3.7V. If your product prints a different voltage, enter that instead.

Take two 20,000mAh units. 20,000mAh × 3.7V ÷ 1000 = 74Wh, which is within 100Wh, so no approval is needed, and two units fit inside the limit of 2 per person. Pack three of the same and only 2 may travel, so one stays behind. Power banks are also banned from checked baggage, which means the third cannot be checked in either.

At a rated voltage of 3.7V, 10,000mAh is 37Wh and 20,000mAh is 74Wh, so both travel without approval. 30,000mAh is 111Wh, above 100Wh, and needs the airline's approval. The no-approval band reaches roughly 27,027mAh, and above roughly 43,243mAh the unit exceeds 160Wh and cannot be carried. A 50,000mAh unit is 185Wh, which puts it in that last group.

If the product shows only mAh and its voltage is not 3.7V, the watt-hours change. The same 20,000mAh at 5V is 100Wh, which is still within 100Wh and fine without approval, but at 5.1V it becomes 102Wh and moves into the approval band. So when you are choosing a capacity close to a boundary, check the Wh figure printed on the product. Where a Wh figure is printed it governs and takes priority over this conversion. The count is 2 per person whatever the capacity, so plan on meeting your needs within 2 units instead of carrying several small ones.

The verdict rests on 국토교통부 보도자료 (8 April 2026). The ICAO Council approved an amendment on 27 March 2026 that added limits on the number of power banks and a ban on charging and using them on board to the ICAO Technical Instructions (Doc 9284), and Korea applied it from 20 April 2026. From that date, charging a power bank on board and using one to charge another device are both banned.

The ministry has since written the same rule into its notice 항공위험물운송기술기준. Ministry notice No. 2026-584 (a full revision, issued and in force from 22 October 2026), in the lithium battery entry of 별표 28, requires airline approval over 100Wh and up to 160Wh, and says power banks travel only in cabin baggage, at most 2 per person, and may not be charged on board or used to charge other devices. When not in use, each one stays in its retail packaging, has its exposed terminals taped, or goes in its own plastic bag or protective pouch to prevent a short circuit. The previous notice described the approval band as under 160 watt-hours, a hair away from the press release. The amended notice says 160Wh or less, so exactly 160Wh falls in the approval band (notice text retrieved 29 October 2026). Batteries installed in a device such as a laptop or camera are covered by a separate clause of the same entry and are outside this calculator.