Free online text deduplication tool. Quickly remove duplicate lines, supports ignore case, sort and more options.
TL;DR: Free text deduplication tool for line-based dedup. Supports case sensitivity, whitespace trimming, and first/last occurrence order, runs locally.
For local tools, open DevTools → Network and search your input — it should not appear in requests.
Usage Guide
Deduplicate lines locally with normalization, keep policy, sort modes, and optional counts.
1. Use
Paste lines, choose normalization/keep/sort, copy unique lines or TSV counts.
2. Not cleaning
Deduping is not spelling repair — normalize first.
3. Limits
Whole-line identity; use column tools for tabular keys; NFC helps Unicode lookalikes.
4. First vs last
Pick consciously; inspect collisions via counts.
5. Sort
Preserve order for audit; frequency to find hot rows.
6. Privacy
Contact lists stay local — store outputs carefully too.
FAQ
Yes. Every dedupe pass runs entirely in your browser, and nothing travels through any server. The exported file still holds the same personal data, though, so store it with the same care as the original list.
Line-based dedupe with ignore-case, trimming, collapsed internal whitespace, and Unicode NFC normalization; keep the first or last occurrence; original, alphabetical, or frequency ordering; duplicate counts; and export as txt or a count TSV.
It depends on the source: merged logs usually keep the last occurrence (the newest state), while merged rosters keep the first (the earliest record). The wrong choice silently drops the line you wanted — inspect conflict lines in the count view before settling on a policy.
No. Dedupe only handles lines judged to be "the same" — it fixes no typos and fills no missing fields. Normalize case and whitespace first and pin down what counts as the unique key in your business, then dedupe; the duplicate counts can also point you back to dirty data sources.
This tool compares whole lines by default. For multi-field rows, switch to a spreadsheet-style tool that dedupes by column, or extract the key column first. NFC normalization is what catches "identical-looking" accented-letter differences.
Yes. Relative input order is preserved under your keep policy by default, which keeps before/after comparison easy. You can switch to alphabetical order for manual scanning, or sort by occurrence count — abnormally frequent lines usually mark spam or a dirty source.
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