Compare two flags
Pick any two of the 196 national flags and see them at full size next to each other, with every attribute they share and every one they differ on called out — including the single fastest way to tell them apart.
Commonly confused pairs
Choose two flags — or tap one of the commonly confused pairs above.
Told them apart?
One flag a week, the real story behind it, and a quiz link to make it stick. No spam.
How the comparison is worked out
Every row in the table is measured from the flag artwork itself rather than typed in by hand. Each of the 196 flags is rendered and its pixels sampled, which gives the colours actually present and the share of the field each one covers; the layout and band count come from scanning across the rendered image. That means a comparison is available for any pairing you can think of, not just the pairs somebody has written about.
A colour has to cover at least 4% of the flag to be listed as one of its colours. Below that threshold it is an emblem detail — the small amounts of red and gold inside a coat of arms, for instance — and it is deliberately excluded, because saying two flags “share red” when one of them only has red inside a crest three centimetres wide is not a useful thing to tell somebody trying to tell them apart.
Why some pairs come with a written explanation
The “commonly confused pairs” buttons and the note that appears above the table for those pairings are not computed. They come from the look-alike sections written on the individual country pages, which explain the specific historical reason two designs resemble each other — shared independence-era palettes, a common colonial ensign, a deliberate borrowing, or in several well-known cases pure coincidence. Chad and Romania are the classic example: near-identical vertical tricolours with entirely unrelated origins and a genuine diplomatic history of complaint about it.
A computed diff can tell you Chad's blue is a shade darker. It cannot tell you that the resemblance is coincidental, that Romania's design predates Chad's independence, or that the two governments have actually discussed it. That is why the authored explanation is shown above the table rather than replaced by the numbers.
Reading the attribute table
Rows marked ● same are where the two flags agree; rows marked ○ differ are where they do not. The summary line above the table counts both, and the line below it names the colours unique to each flag — in practice that is the single most useful sentence on the page, because a colour only one of the two flags has is the fastest thing to look for when you are staring at a flag on a screen and trying to decide which of two candidates it is.
The share-count is a summary of the rows, not a claim about how similar the flags look to the eye. Two flags can agree on five of six attributes and still be immediately distinguishable because of an emblem the table treats as a single yes-or-no. Trust the images and the difference line over the count.
If you are not yet down to two candidates, start from the flag identifier and describe what you remember instead. For the wider set of resemblances with the reasoning behind each, the flags that look alike guide covers the families rather than individual pairs, and the look-alike challenge tests whether you can actually tell them apart under time pressure.