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Free tool · LinkedIn ABM
SHA-256 Email Hasher
Paste emails or upload a CSV with an email column. The tool normalises each address the way LinkedIn or Google documents, hashes it with SHA-256 on your device and gives you an upload-ready CSV.
- Free, no sign-up
- Runs in your browser
- Checked 19 October 2026
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How it works
How to use the SHA-256 Email Hasher
- Choose LinkedIn or Google Customer Match.
- Paste or upload the list; the email column is found automatically.
- Download the hashed CSV and upload it to the platform.
| What | How it's worked out |
|---|---|
| Lowercase, remove all whitespace, SHA-256 hex | |
| Lowercase, remove whitespace, remove dots before @ in gmail.com and googlemail.com, SHA-256 hex | |
| Already hashed | 64-character hex values are kept as they are |
| Header | email for LinkedIn, Email for Google |
From our media team
How to use the result
- Hashing isn't anonymising. Common addresses can be guessed by hashing candidates. Handle the file as personal data and delete it after upload.
- Work emails match less often than personal ones on consumer platforms. Add company lists alongside contact lists for B2B.
- Check your legal basis before uploading customer or prospect data to an ad platform.
Read next
- Hashed email matching for B2B: LinkedIn contact lists and Google Customer MatchHow to prepare email lists for LinkedIn contact targeting and Google Customer Match: the normalisation each platform documents, SHA-256 hashing, file headers and…
- Is company identification legal in the UK and US?The rules that apply to identifying the companies that visit your website in the UK and US: PECR consent, UK GDPR, US state privacy laws and practical safeguards.
- Which roles to target on LinkedIn at companies that came from AIYou know the company, not the person. How to choose LinkedIn job functions and seniority for each AI-identified account from the pages it read, and how to group…
- Target account list hygiene: clean lists match better and cost lessWhy messy account lists waste ABM budget and how to clean them: one domain per company, duplicates and subsidiaries, free email domains, customer exclusions,…
Questions
Straight answers.
Does LinkedIn require hashed emails?
LinkedIn's API documentation says emails in contact lists must be SHA-256 hashed, after lowercasing and removing whitespace. It lists 10,000 rows as the minimum for API uploads, and an audience needs 300 matched members to serve.
How does Google normalise emails for Customer Match?
Google asks for lowercase addresses without spaces, with dots removed before the domain in gmail.com and googlemail.com addresses, hashed with SHA-256.
Is anything uploaded?
No. Hashing uses your browser's Web Crypto API. Nothing is sent to AnswerBid.
Can a SHA-256 hash be reversed?
Not directly, but common addresses can be found by hashing guesses and comparing. That's why hashed lists are still personal data.
More free tools
Related tools
Sources: LinkedIn Marketing API: Matched Audiences list uploads (Microsoft Learn); Google Ads Help: Create a Customer Match list by uploading a data file.
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