Remove duplicate characters

Client

Keep the first occurrence of each character—distinct from duplicate line removal.

Character vs line dedupe

This tool keeps the first occurrence of each character in order—optional case folding treats A and a as one symbol. It does not remove duplicate lines; use remove duplicate lines for row-level cleanup.

Typical cleanup flows

Collapse repeated punctuation in messy paste, then align columns on align text columns or compare overlap with Jaccard similarity before deeper NLP steps.

Nearby workflows on Toolcore

Common use cases

  • Collapse repeated punctuation in messy paste.
  • Build unique character sets for puzzles or tests.
  • Quick cleanup before line-level dedupe tools.

Common mistakes to avoid

  • Confusing with line dedupe

    This operates on characters, not whole lines.

  • Unicode combining marks

    Each code unit is deduped separately—normalize first if needed.

FAQ

Remove duplicate lines?

Use remove duplicate lines for row-level dedupe.

Case-insensitive?

Toggle case-sensitive dedupe off to fold A/a together.

Common search terms

Phrases people search for that match this tool. See the full long-tail keyword index.

  • remove duplicate characters online
  • unique characters string tool
  • dedupe letters preserve order browser
  • collapse repeated chars in text

More tools

Related utilities you can open in another tab—mostly client-side.