File organization tool
OneDrive Filename Validator
Check filenames locally for reserved characters, trailing spaces and other common OneDrive sync risks.
Processing happens in this browser tab. The pasted data is not submitted to ClearCopies.
Line-by-line validation
Specific issue labels
Local-only processing
How it works
A useful answer in three clear steps.
- 1
Paste filenames without full paths
Complete this check before moving to the next decision.
- 2
Review each flagged rule
Complete this check before moving to the next decision.
- 3
Rename at the source before upload or migration
Verify the final result against your current cloud drive or organizational policy.
Frequently asked questions
Before you use this tool
Is the Filename Validator free to use?
Yes. You can use this tool in the browser without creating an account or installing software.
Does ClearCopies upload the data I paste?
No. This utility processes the pasted text in your current browser tab. Avoid pasting secrets, access tokens or unredacted exports into any online tool.
Can this tool delete or change my cloud-drive files?
No. This page does not connect to your cloud account and cannot rename, move or delete files. It produces an estimate, analysis or checklist for you to review.
What should I do after using the Filename Validator?
Rename at the source before upload or migration. Microsoft naming restrictions can vary by tenant, platform and product update; test critical migrations in the target environment.
Keep exploring
Related file organization tools
Path Length Checker
Measure pasted OneDrive paths and flag entries that exceed a conservative length threshold.
Filename Sanitizer
Create safer filename suggestions by replacing reserved characters and trimming risky endings.
Duplicate Name Resolver
Generate deterministic numbered names for repeated filenames without overwriting the original list.
Ready to measure duplicate storage with real data?
Choose OneDrive or Dropbox for a read-only scan, then review exact fingerprint matches before any cleanup decision.