Does it rename files automatically?

No. It prepares cleaner file-name suggestions in your browser so you can copy them before uploading or renaming files elsewhere.

Can it keep Korean or non-English names?

Yes. It mainly removes risky punctuation and normalizes separators. Existing Hangul, Latin letters, and numbers can stay.

Can I process multiple lines at once?

Yes. Add one title or file name per line, then apply numbering and date rules to the whole batch.

How are duplicate file names handled?

When duplicate adjustment is turned on, the tool appends a number to repeated results to reduce naming conflicts. Before applying the names, still check whether the destination folder already contains the same names.

Can it shorten very long file names?

Yes. Set a maximum length and the tool trims the base name while keeping preserved extensions and duplicate suffixes at the end.

TOOLOG TOOL

Filename Sanitizer | Remove symbols, keep extensions, trim long names, and fix duplicates

Paste titles or file names to normalize spaces, special characters, repeated separators, extensions, date prefixes, sequence numbers, long names, and duplicate candidates into safer copy-ready file names.

Text/File Naming

Titles or file names

Separator style

Letter case

Add date prefix

Date

Add sequence number

Starting number

Remove emoji/decorative symbols Keep extensions Make duplicate names unique

Maximum name length

Long names are shortened before duplicate suffixes are added, while preserved extensions stay at the end.

0Input items

0Output items

0Changed

0Duplicate candidates

Paste file names to normalize spaces, symbols, numbering, and duplicate candidates.

Up to 200 non-empty lines are processed. Starting number must be 1-9999, and maximum name length must be 20-255 characters.

Cleaned file names

Why use a filename sanitizer?

When you handle documents, screenshots, thumbnails, and attachments, messy file names often become a small but constant source of friction. In shared folders, blog uploads, and submission packages, consistent naming rules make files easier to sort, search, and reuse.

This tool helps you:

normalize spaces and special characters
unify separator style
add a date prefix and sequence numbers
keep common extensions such as .png, .pdf, and .xlsx
shorten names that exceed your chosen maximum length
make duplicate filename candidates unique
copy a cleaner output list for the next step

How to use it

Paste titles or file names, one per line.
Choose hyphen, underscore, or no separator.
Optionally force English letters to lower/upper case.
Turn on date prefix, sequence numbering, extension keeping, maximum length, and duplicate adjustment as needed.
Review the cleaned list, then copy it for folder cleanup, uploads, or batch rename preparation.

Why this tool was improved today

Recent quality passes focused on tools such as Online Return Package Checker, Fraction Calculator, Body Fat Calculator, Emergency Bag Checklist Planner, Pomodoro Timer, and Parking Fee Calculator, so this pass avoided repeating them. Filename Sanitizer has several error-prone filename edge cases, including special characters, compound extensions, duplicate suffixes, and long upload names, making it a good candidate for a focused UI, SEO, and validation pass.

Especially useful for

1) Blog or CMS asset uploads

Clean thumbnail, screenshot, and post-asset names before uploading them to a blog or CMS.

2) Assignment and submission files

Make report titles, version labels, and submission dates follow one predictable file-name rule.

3) Shared team folders

Apply a simple naming pattern before a shared folder becomes hard to search or sort.

To clean pasted title lists first: Text Line Break Cleaner
To adjust English case rules separately: Case Converter
To check drafts for personal data before sharing: Privacy Exposure Checker

Rules and limits

Characters that often cause filename problems, including / \ : * ? " < > |, are treated like separators.
With extension keeping enabled, common final extensions such as .png, .pdf, .xlsx, .tar.gz, and .min.js are preserved as much as possible.
Names longer than the maximum length are shortened from the base name first so preserved extensions and duplicate suffixes remain at the end.
To avoid browser slowdowns, only the first 200 non-empty lines are processed.
This tool does not rename real files. Copy the cleaned names and apply them in your upload or batch-renaming workflow.

FAQ

Does it add extensions automatically?

If an extension like .png or .pdf is already present, the tool keeps it. If there is no extension, it only cleans the name itself.

Can I use my own date instead of today?

Yes. You can leave the date off, use today, or choose a custom date to prepend.

Do I have to remove all special characters?

Not always, but replacing risky punctuation with safer separators usually reduces upload and compatibility problems.

Are duplicate names changed automatically?

If duplicate adjustment is enabled, repeated results get suffixes such as -2 and -3. The tool does not scan your actual folder, so confirm the final names before applying them.

Are compound extensions kept?

Common compound extensions such as .tar.gz, .min.js, and .d.ts are treated as one extension. Dotfiles such as .env are kept as names instead of being misread as empty names with extensions.

Summary

The Filename Sanitizer is a browser-based utility for turning messy titles or inconsistent file names into safer, rule-based names for uploads, sharing, and batch rename preparation.