About the Thousands Separator Tool
Paste a list of numbers, one per line, and add or remove thousands separators in one go. Choose commas (1,000), dots (1.000), spaces (1 000) or apostrophes (1'000), and pick standard grouping in threes or Indian grouping, where the last three digits are followed by groups of two, as in 12,34,567. The tool also reads numbers that already have separators, in either the English style (1,234,567.89) or the European style (1.234.567,89), and keeps the decimal part intact. It works on the digits as text, never as floating-point numbers, so long values such as account numbers or 25-digit figures are never rounded. Lines that are not numbers are left alone and reported.
Updated October 2026
How to use the Thousands Separator Tool
- 1Paste or type your numbers, one per line.
- 2Tell the tool how your numbers are written, or leave it on automatic.
- 3Choose Add separators or Remove separators.
- 4Pick the separator, the decimal mark you want in the result and, when adding, the grouping style.
- 5Check the result and the note about any lines that were not numbers, then copy it.
How thousands separators work
Large numbers are hard to read without grouping. Is 10000000 ten million or one million? A separator every three digits, as in 10,000,000, makes it obvious. Different countries use different characters: the United States and the United Kingdom use a comma, Germany and much of Europe use a dot or a space, and Switzerland uses an apostrophe. The decimal mark is the reverse of the separator in many places, so 1,234.56 in English is written 1.234,56 in German. This tool lets you pick both.
Standard versus Indian grouping
Standard grouping splits digits into threes from the right: 1,000, 1,000,000 and 1,000,000,000. Indian grouping keeps the last three digits together and then groups in twos: 1,000, then 10,00,000 (ten lakh), then 1,00,00,000 (one crore). If you write amounts in rupees for Indian readers, or copy figures from Indian reports, this is the style to choose. The numbers themselves are the same either way; only the commas move.
Tips for lists
- Put one number on each line. Blank lines are kept so your list keeps its shape.
- You can paste numbers that already have separators and change them to a different style in one step.
- Use the input style box when a list is written with commas as decimal marks, such as 3,14.
- Choose the none option for the separator, by switching to Remove separators, to get plain digits for a spreadsheet or database.
- Negative numbers keep their minus sign, and a result of minus zero is shown as 0.
Related tools
The Sort Numbers tool puts a list in order, the Number to Words tool writes a value in English, the Rounding Calculator shortens long decimals, the Number Base Converter changes between binary, decimal and hexadecimal and the Scientific Notation Converter writes very large or small values compactly.
Features
- Comma, dot, space and apostrophe separators
- Standard (1,000,000) and Indian (10,00,000) grouping
- Reads numbers that already have separators
- Keeps decimals and negative signs
- Choose a dot or a comma as the decimal mark
- Works on exact digits, so long numbers are never rounded
- Lists the lines it could not read
Frequently asked questions
What is a thousands separator?
It is a character placed between groups of digits so that large numbers are easier to read. In the US and UK it is a comma, as in 1,000,000. Many European countries use a dot or a space, and Switzerland often uses an apostrophe.
What is Indian number grouping?
In Indian grouping the last three digits form a group and every group before that has two digits. So 1234567 becomes 12,34,567. This matches the lakh (1,00,000) and crore (1,00,00,000) system used in India.
How do I remove commas from a list of numbers?
Switch to Remove separators and paste your list. The commas, spaces and apostrophes used for grouping are taken out and the decimal part is kept, so 1,234,567.89 becomes 1234567.89. If your numbers use the European style, set the input style to comma as the decimal mark.
How does the tool tell a decimal mark from a separator?
On automatic, if a number has both marks, the last one is the decimal mark. If it has several of the same mark, those are separators. A single comma followed by exactly three digits after one to three digits is treated as a separator (1,234), and any other single mark is a decimal mark (3,14 and 1234.5). A single dot is always read as a decimal mark. If your list is ambiguous, set the input style yourself.
Why was one of my lines left as it was?
Only plain numbers are changed. A line with letters, a currency symbol, scientific notation like 1e5, or separators in odd places such as 1,23,4567 is left exactly as typed, and the tool lists its line number so you can fix it.
Can it handle very long numbers?
Yes. The digits are handled as text and never converted to a floating-point number, so a 30-digit value comes out with every digit unchanged. A spreadsheet would round the same value after 15 digits.