The following table shows the aspect ratio (height to width ratio) of national flags used by countries and dependencies. Variant flags such as ensigns are listed in the "Alternative flags" column, if they have different proportions from the national flag. Territories without an official flag distinct from that of their controlling country are excluded.
The ratios used most commonly are 2:3, used by 89 of 195 sovereign states, and 1:2, used by 54 sovereign states. Most dependencies and former colonies use the same proportions as their mother countries: all British Overseas Territories use 1:2 ratios, while the flags of most former and current Dutch and French areas have 2:3 proportions.
For comparison, the ratios are also given as a decimal number, which is the flag width divided by its height (e.g. a 2:3 flag has a decimal ratio of 3/2 = 1.5). Flags with irrational ratios have only a decimal approximation, and have the exact form given in the "Notes" column.
Legend:
Click on the "Flag" header to sort by status: first sovereign states, then de facto countries, then dependencies.