Here’s a helpful trick if you’ve ever struggled to find an old Gmail contact or unsaved number on Android: it turns out that Google keeps a list of every Gmail account you’ve ever sent or received an email from, including those you don’t save to your contacts, as “Other Contacts.”
This list is easy to find on the web, but it’s now possible to look up unsaved “Other Contacts” on your Android devices through the Contacts app. It appears this feature arrived a few updates ago, but it was only officially mentioned by Google in the February 12, 2020 update to the app (version 3.17.1).
How to find ‘Other’ contacts on the web
Go to contacts.google.com/other (sign in with your Google account if prompted)
Trim as necessary. If your list is huge and you’re only looking to whack a few names off your list—or combine any information with existing contacts—use the search feature to isolate down to specific people. Google’s includes any publically saved contact info (such as their name, email address, and phone number, if available).
How to find ‘Other’ contacts on your Android device
Open the Contacts app.
Type the contact’s name or email address into the search bar.
The search results should auto-populate with suggested contacts that match your search, first showing “Saved” contacts then “Other” contacts from Google’s list.
Tap a listing for more details. You’ll be able to add it to your official contacts, but you won’t be able to remove it from your “Other” list. To do that, you’ll need to pull up the aforementioned website.
Note: searching by phone number will only turn up “Other” contact results if that number is tied to an account in the Other contacts list or is tied to a publically-available Google contact (such as a business listed on Google Maps). Otherwise, searching by phone number will only show unsaved numbers you’ve called or received calls from, and it won’t show personal contact information.