Batch file renamer
Rename files by rule in one go, and generate name lists and dummy filesNew names
You see the result before anything is applied. Duplicate names are flagged — fix the rule before downloading.
Choose files and the new names appear here.
Names to be created
What is this for
For testing upload limits, transfer speed and storage behavior. The file is built in browser memory and downloaded directly — it never touches a server.
- It is built whole in browser memory, so 512MB is the ceiling.
- Empty content fills with zeros — which compresses to almost nothing, so put some text in for compression tests.
About this tool
Rename many files at once by rule, extract a list of names, and generate dummy files for testing. Use it to tidy the names of a few hundred photos, or when you need a file of a specific size to test an upload limit.
How to use it
- 1 Choose the files to rename — you can drop a whole folder.
- 2 Set the rule — numbering, prefixes and suffixes, find-and-replace, extension changes, in any combination — and see the result in a table before applying it.
- 3 Download a ZIP with the new names, or copy just the list of names as text.
Good to know
- Your originals are never overwritten — renamed copies come out as a new ZIP
Frequently asked questions
How do I put a sequence number in the name?
Write {n} in the rule and the number goes there. You can set the starting value and the digit count, so zero-padded forms like 001, 002 work too.
What are dummy files for?
For testing upload limits, transfer speeds and storage. Pick a size and you get a file of exactly that size, filled with meaningless data.
Can I do this with a lot of files?
A few hundred files is fine. If the total is very large — dozens of big videos, say — it is safer to work in batches.
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