Number Formatter
Adds or removes thousand separators, rounds to a set precision and formats as currency or percent by locale.
Adds or removes thousand separators, rounds to a set number of places, and formats as currency or percent. It also reads a formatted number back, which is the harder half: 1.234,56 is a thousand and a bit in Germany and one and a bit in Korea.
Numbers
One per line, in whatever convention they were written in — this is the tool you open because they are in somebody else’s. Thousands separators, currency symbols, accounting parentheses and Korean 만/억 suffixes are all understood.
Format
2.5 → 3. What school taught.
Formatted
converted
5
left alone
1
lines that are not numbers
first value in 만/억
123만 4567
Reading is the harder half. 1.234,56 is one and a bit in Germany and one thousand two hundred in the United States — the same characters, opposite jobs. The rule used here is positional: whichever of . or , appears last is the decimal separator, because a group separator can never be the final one. That reads all four common conventions correctly without asking where you are. One shape it cannot settle on its own — a single mark with exactly three digits after it — is settled by this page’s own language: here 1,234 is one thousand two hundred and thirty-four and 1.234 is one and a bit.
Rounding to 2 places gives 1.01 for 1.005 here. (1.005).toFixed(2) gives 1.00, because the double nearest 1.005 is a hair below it — this rounds through the decimal literal instead.
Preview
- 1,234,568 — whole
- ₩1,234,567.89 — currency
- 123,4567.891 — grouped in 만
- 123만 4567 — read in 억/만
- 1234567.8910 — plain
A few common shapes of the first number in the list.
How to use it
Paste the number or numbers
One per line for a column. Formatted input is read back as well as written out.
Say which separators to write with
This setting is about what comes out: whether the tool writes 1,234.56 or 1.234,56. What goes in is read from the digits themselves — whichever of . or , comes last is the decimal — so a number in somebody else’s convention converts without you telling the tool where it came from. There is one shape the digits cannot settle, a single mark with exactly three digits after it, and that one follows this page’s own language: here 1,234 is one thousand two hundred and thirty-four and 1.234 is one point two three four.
Choose the rounding
Half-up is what people expect; half-even — banker’s rounding — is what accounting systems use because it does not drift upward over a long column.
Common questions
Why does 1.005 round to 1.00?
Because 1.005 cannot be stored exactly in binary — the stored value is very slightly below it, so rounding half-up correctly gives 1.00. Every language does this; it is arithmetic rather than a bug, and it is why money is kept in integer units.
How do I read a Korean 억 or 만?
The preview shows the number grouped by 만 and 억 as well as by thousands. Korean groups by four digits and Western notation by three, which is why 100,000,000 is awkward in one and 1억 is obvious in the other.
Which locales are supported for currency?
The browser’s own locale data, so whatever your browser knows. That means the symbol, its position and the separators all come from the same place your operating system gets them, rather than from a table here that could go stale.
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