ISEMAIL Function in Google Sheets: Formula, Examples & Troubleshooting
Check email-address format with ISEMAIL in Google Sheets. Flag ordinary mistakes, separate blank entries, and avoid claiming mailbox verification.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: =ISEMAIL(A2) checks whether A2 follows a commonly accepted email-address format. A TRUE result does not establish that the mailbox exists or can receive a message.
Verification: NOT_TESTED_IN_GOOGLE_SHEETS. Google’s reference was reviewed October 17, 2026. The simple examples are independently reasoned format checks, not native evaluations, delivery tests, or mailbox lookups.
Syntax and scope
=ISEMAIL(value)
The one required input is the value to inspect. Supply a cell reference or quoted address text, for example =ISEMAIL("reader@example.com"). There are no documented optional arguments, domain allowlists, or mailbox-verification settings. Google ISEMAIL reference.
The function answers a format question. It cannot establish ownership, consent to contact, current inbox availability, or whether the address belongs to the intended person. Those questions require separate evidence.
Google’s current examples include a .xyz address as well as .com. Do not invent a .com-only rule or assume that a short list of older domain endings defines the function’s current contract.
Example: review a small import
Put these synthetic strings in A1:B5:
| Row label | Address text |
|---|---|
| Entry 1 | reader@example.com |
| Entry 2 | reader.example.com |
| Entry 3 | @example.com |
| Entry 4 | reader@ |
- Put
Format checkin C1. - Put
=ISEMAIL(B2)in C2 and fill down through C5. - Compare with the expected simple-case results below.
- Review failed rows in the original source rather than guessing missing characters.
| Address text | Expected result | Reason for the expectation |
|---|---|---|
| reader@example.com | TRUE | Ordinary local-part and domain structure |
| reader.example.com | FALSE | Missing @ separator |
| @example.com | FALSE | Missing local part |
| reader@ | FALSE | Missing domain |
These examples deliberately avoid disputed or less-common email syntax. They are not a complete implementation of Google’s validator, an email standard, or a substitute for native testing of a particular edge case. The example-domain address is illustrative; no message should be sent to it as part of this exercise.
Advanced use: keep missing data separate from malformed data
An import review benefits from three labels rather than a single accepted/rejected flag. In D2, use:
=IF(B2="","Missing",IF(ISEMAIL(B2),"Format looks valid","Review format"))
Fill down alongside the import. For the four sample rows, the expected labels are Format looks valid, Review format, Review format, and Review format. A fifth row whose input is deliberately an empty string should receive Missing.
The first comparison is an empty-string check, not a claim that every visually blank cell is physically empty. Keep whitespace-only or special-character cases for inspection instead of silently treating them as missing.
This formula leaves the original address untouched. That matters because an automatic “correction” can create a different plausible address belonging to somebody else. A useful workflow flags the exact row, shows the supplied value, and asks for a correction through an appropriate existing process.
What to do with TRUE and FALSE
A TRUE result can support a low-stakes formatting check before a human reviews the record. It is not a delivery guarantee. A FALSE result is a reason to inspect the value; it does not justify replacing unusual but intentional addresses with a made-up alternative.
For any application that must support uncommon address syntax, test the actual requirements separately. The reviewed help page does not publish a complete parsing grammar or specify every case involving internationalized addresses, quoted local parts, address lists, display names, plus tags, trailing spaces, or error-valued cells. This guide does not assert results for those unverified cases.
Do not recreate ISEMAIL with a short regular expression and call it equivalent. A custom regex defines its own acceptance rules, and those rules may differ from the product’s implementation or the destination system’s requirements.
Troubleshooting
- The format passes but delivery fails: Existence and deliverability are outside ISEMAIL’s documented scope.
- A familiar contact name fails: The function expects an address value. A display name or a combined name-and-address string is not covered by the simple examples here.
- The input is quoted incorrectly: Quote literal text, but leave a genuine cell reference such as B2 unquoted.
- An unusual address fails: Inspect the exact original string and the downstream system’s requirements. Do not infer a universal email-standard violation from this one test.
- Missing and invalid entries are mixed together: Use a separate missing-data label so reviewers know what kind of correction is needed.
Availability and related guides
Google currently documents ISEMAIL; its introduction date and any retirement or last-working version were not established. No Excel built-in equivalent, regex parity, or other-product validator compatibility is assumed.
See IF for review labels, ISTEXT for a separate type check, ISBLANK for physical blankness, and COUNTIF to count a saved set of review labels.
First-party references reviewed October 17, 2026: ISEMAIL and IF.