Email list dedupe

List / data tools

Remove duplicate email addresses (case-insensitive, trimmed). See before / after / removed counts, then copy or download. Everything runs in your browser; your data is never uploaded.

What is this email dedupe tool?

A free, browser-based tool that removes duplicate email addresses from a list. Paste one email per line and it collapses duplicates — matching case-insensitively and ignoring surrounding whitespace, so '[email protected]' and '[email protected]' count as one. It shows the before, after, and removed counts, and lets you copy or download the cleaned list. Everything runs locally in your browser, so your addresses are never uploaded.

How to use it

  1. Paste your email list (one address per line) into the box on the left.
  2. Read the before / after / removed counts on the right to see how many duplicates were found.
  3. Copy the cleaned list to your clipboard, or download it as a text file.

Common use cases

  • Cleaning a contact list before importing it into an email tool or CRM.
  • Merging several signup or export files and removing the overlapping addresses.
  • Avoiding sending the same campaign twice to the same person.

Other list tools

Operated by

unbounded pioneering inc
Timothe AI

Tools by Timothe AI is a suite of free tools built and operated by unbounded pioneering inc, the company behind Timothe AI.

Ryosuke Suzuki
Ryosuke SuzukiFounder & CEO

Founder & CEO of Unbounded Pioneering Inc., the company behind Timothe AI, and an expert in machine learning and AI product development. He began his career in machine learning research at a university laboratory, then designed and built large-scale products as a software engineer at PLAID, Rakuten, and Recruit, while also driving new business development. Now specializing in generative AI and AI products, he works across both engineering and business development, and is a named inventor on multiple granted patents in web technology.

Named inventor on granted patents JP6887648 & JP7480958 · Patent pending on Timothe AI technology

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