Tally Counter

Tally marks are the oldest counting notation still in daily use, and they survive for a good reason: you can add to them without re-reading what you've written, and you can count the result in fives at a glance rather than one at a time. This counter draws them the standard way — four vertical strokes, then a fifth struck diagonally across the group.

Why fives

Grouping in fives is a readability trick. A row of nineteen individual strokes has to be counted stroke by stroke; three completed gates and four loose strokes reads as nineteen almost instantly, because the brain counts the groups and adds the remainder.

That's the same reason the notation appears everywhere from scorekeeping to fieldwork to prison walls in films — it's optimised for adding one at a time and reading the total quickly, which is precisely the tradeoff a counter needs.

Tally marks around the world

The five-bar gate is the Western convention. It isn't universal: in China, Japan and Korea counting is often done by drawing the character 正, which takes exactly five strokes, so one completed character means five. In parts of South America a five-stroke box shape is used instead — four sides and a diagonal.

All three encode the same idea, a shape completed in five strokes, because five is about the largest group a person can recognise without counting.

When to use marks instead of a number

Tally mode is genuinely better when someone else has to read the count over your shoulder or from a distance — a scoreboard, a stocktake sheet, a survey clipboard — because the groups are legible at a glance without focusing on digits.

Plain numbers are better past a few dozen, and the counter switches over in one tap under Settings when the marks stop being practical.