Turn 1, 2, 3 into 1-3
Compress or expand consecutive number ranges
Shorten a long number list, or turn short ranges back into every number.
Free browser tool
Choose what to do with your numbers
Paste whole numbers or ranges, then choose Shorten or Expand.
Processed in your browser
Copy or download the result
No account. No signup.
Worked examples
Number range examples and rules
These examples show exactly what sorting, minimum run length, negative numbers, and descending ranges do.
| Goal | Input and settings | Result |
|---|---|---|
| Compress a basic list | 1, 2, 3, 7, 8, 9, 15; minimum 3 | 1-3, 7-9, 15 |
| Keep a two-number run separate | 4, 5, 9; minimum 3 | 4, 5, 9 |
| Compress negative numbers | -5, -4, -3, -2, 4; minimum 3 | -5--2, 4 |
| Expand in descending order | 12-10, 20; Expand | 12, 11, 10, 20 |
This tool accepts whole numbers only. Expansion is limited to 100,000 output numbers so an accidental giant range cannot freeze the page.
Optional guide Learn more about this tool Open the full explanation and detailed steps.
How to compress consecutive numbers
The tool reads whole numbers, finds runs where each value is exactly one more than the last, and replaces long enough runs with their first and last values.
Paste whole numbers or ranges
Use spaces, commas, semicolons, or new lines. Negative numbers and descending ranges such as 12-10 are supported.
Choose compress or expand
Compress can sort and remove duplicates before finding runs. Expand follows each range in the direction it is written.
Choose when a run becomes a range
A minimum of 3 changes 4, 5, 6 to 4-6 while leaving 9, 10 as two separate values.
Quick example
Compress an ID list
The example turns 1, 2, 3, 7, 8, 9, and 15 into 1-3, 7-9, 15.
Common questions
Shorten a number list FAQ
Can the range compressor handle negative numbers?
Yes. It can compress or expand negative whole numbers, including ranges such as -5--2.
Will the tool sort and remove duplicates?
Those options are on by default when compressing. Turn either one off when the original order or repeated values must be preserved.
What does minimum range length mean?
It is the number of consecutive values required before a run becomes a range. With a minimum of three, 4, 5, 6 becomes 4-6 but 9, 10 stays separate.
Are my number lists uploaded?
No. The list is processed in your browser and is not saved by default. Use Save on this device to keep it here, or download a backup file.