21 guides · native method first
Guides: remove duplicates from anything
Every guide starts with the method built into the platform you already have, whether that's a formula, a menu, or a preinstalled app. Only then does it cover where our free in-browser tools genuinely help. No fake urgency, no app installs where none are needed.
/guides/duplicate-photos
Duplicate photos on any device
The hub: why no website can clean your camera roll, and the built-in method for iPhone, Android, Google Photos, Mac and Windows.
Read the method →/guides/what-is-dedupe
What does dedupe mean?
A plain definition: exact versus fuzzy matching, where deduplication shows up, and which copy you should keep.
Read the method →/guides/remove-duplicates-google-sheets
Remove duplicates in Google Sheets
UNIQUE for a live clean copy, Data cleanup for in-place deletion, and when fuzzy matching earns its keep.
Read the method →/guides/remove-duplicates-excel-formula
Excel duplicate formulas
COUNTIF and COUNTIFS helper columns, UNIQUE in Excel 365, and when the button beats the formula.
Read the method →/guides/find-duplicates-in-excel
Find duplicates in Excel
Highlight before you delete: conditional formatting, COUNTIF flags, filtering by colour, and the four cases all of it misses.
Read the method →/guides/how-to-use-dedupe-dev
How to use Dedupe.dev
A walkthrough of all three tabs: the key column chips, the header and case options, and what the result contains.
Read the method →/guides/clean-csv-before-import
Clean a CSV before import
The pre-import checklist: why importers reject files, picking the key column, and what to do about near-duplicates.
Read the method →/guides/dedupe-crm-contacts
Dedupe CRM contacts
Salesforce and HubSpot backlogs: export to CSV, dedupe on email, re-import safely.
Read the method →/guides/iphone-duplicate-photos
Duplicate photos on iPhone
iOS 16+ finds them for you: Photos → Albums → Utilities → Duplicates → Merge. No app needed.
Read the method →/guides/android-duplicate-photos
Duplicate photos on Android
Files by Google is already on your phone: Clean tab → Duplicate files → review → delete.
Read the method →/guides/google-photos-duplicates
Google Photos duplicates
What's automatic, what's manual, and the 60-day Trash rule that actually frees storage.
Read the method →/guides/mac-duplicate-files
Duplicate files on Mac
Finder Smart Folder triage, free open-source dupeGuru, and the safety rules before deleting.
Read the method →/guides/remove-duplicates-notion
Notion database duplicates
No native dedupe: group to find them, export to CSV to count them, delete in place to keep relations.
Read the method →/guides/remove-duplicate-emails-list
Duplicate emails in a list
Case, plus-addressing and Gmail dots: the variants an exact-match import check never catches.
Read the method →/guides/remove-duplicates-sql
Remove duplicates in SQL
DISTINCT, GROUP BY, ROW_NUMBER for one row per group, and DELETE via a CTE without losing the wrong row.
Read the method →/guides/remove-duplicates-python-pandas
Duplicates in pandas
drop_duplicates with subset and keep, duplicated() for review, and where rapidfuzz fits.
Read the method →/guides/find-duplicate-files-windows
Duplicate files on Windows
No built-in finder: hash and group with PowerShell, plus what to check before installing a free one.
Read the method →/guides/google-sheets-dedupe-api
Automate Sheets dedupe via API
A copy-paste Apps Script that adds a Dedupe menu to any sheet, with exact or fuzzy matching.
Read the method →/guides/dedupe-zapier-make-n8n
Dedupe in Zapier, Make and n8n
The exact webhook settings for each tool. One POST, no app to install.
Read the method →/guides/n8n-dedupe-workflow
n8n workflows, ready to import
Two downloads: a minimal dedupe call, and a pipeline that dedupes then validates a mailing list.
Read the method →/guides/remove-duplicates-outlook-contacts
Outlook duplicate contacts
Clean Up is for email, not contacts. The export, clean and re-import loop that does not double your list.
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