Information
ISERROR Function in Excel
Returns TRUE if the value is any error value.
Syntax
- =ISERROR(value)
Arguments
- value (required): The value to check
Examples
- =ISERROR(A1/B1) - Check for division error - Result: TRUE if error
- =IF(ISERROR(VLOOKUP(...)), 0, VLOOKUP(...)) - Handle lookup errors - Result: Value or 0
Defensive formulas with ISERROR
- Use IS* functions inside IF to branch on blank, error, text, or number cells.
- Prefer [IFERROR](/functions/iferror/) when you only need a fallback display value.
- Error hub: [Fix formula errors](/guides/fix-excel-formula-errors/).
Common errors
- Catches ALL errors
- Use ISNA for just #N/A
Use cases
- Error handling
- Data validation
- Conditional logic
Frequently asked questions
- Should I use ISERROR or IFERROR? Use IFERROR for cleaner formulas: =IFERROR(A1/B1, 0) instead of =IF(ISERROR(A1/B1), 0, A1/B1). IFERROR is shorter and only evaluates the formula once. Use ISERROR when you need the TRUE/FALSE result for other logic.
- What errors does ISERROR catch? ISERROR catches ALL Excel errors: #N/A, #VALUE!, #REF!, #DIV/0!, #NUM!, #NAME?, #NULL!. Use ISNA for only #N/A, or ISERR for all errors EXCEPT #N/A.
Editorial review
- Reviewed by Excel.Directory Editorial Team. Updated May 2026.
When to use ISERROR
- Error handling — common Information scenario for ISERROR.
- Data validation — common Information scenario for ISERROR.
- Conditional logic — common Information scenario for ISERROR.
ISERROR in the Information category
- Browse all Information functions at /categories/information/ for related formulas.
- ISERROR syntax: =ISERROR(value)
- value (required): The value to check
- Confirm ISERROR arguments match the syntax shown above before filling down.
- Lock table and range references with $ when copying formulas across rows or sheets.
Formula checklist before you copy down
- Confirm ISERROR arguments match the syntax shown above before filling down.
- Lock table and range references with $ when copying formulas across rows or sheets.
- If results look wrong, check for text stored as numbers and invisible spaces with TRIM.
- Spot-check three known input rows manually against expected output.
Related Excel functions
- IFERROR (/functions/iferror/): Returns a specified value if a formula evaluates to an error; otherwise, returns the result of the formula.
- ISNA (/functions/isna/): Returns TRUE if the value is the #N/A error.
- ISERR (/functions/iserr/): Returns TRUE if the value is any error except #N/A, otherwise returns FALSE.
Common problems and fixes
- Why Is IFERROR Not Working? (/problems/iferror-not-working/): Wrap the exact expression that produces the error, use IFNA for #N/A only, and fix the source formula before hiding the error message.
- How to Fix a Circular Reference in Excel (/problems/circular-reference-warning/): Use Formulas > Error Checking > Circular References to locate the cell, then break the loop with a separate input cell or iterative calculation only when intentional.
Errors to watch for
- Catches ALL errors — review causes on linked error pages in the directory.
- Use ISNA for just #N/A — review causes on linked error pages in the directory.
Copy-paste audit workflow
- Enter ISERROR on three test rows with known expected output documented on a QA tab.
- Fill down only after absolute references are locked on lookup tables and rate tables.
- Compare against manual calculation or a calculator for financial and statistical functions.
- Search this directory for comparison guides when choosing between similar functions in the same category.
ISERROR worked examples to copy
- =ISERROR(A1/B1) — Check for division error. Expected result: TRUE if error.
- =IF(ISERROR(VLOOKUP(...)), 0, VLOOKUP(...)) — Handle lookup errors. Expected result: Value or 0.
ISERROR reference summary for crawlers and offline review
- ISERROR belongs to the Information category in Excel. Returns TRUE if the value is any error value.
- Full syntax: =ISERROR(value). Open /functions/iserror/ for parameters, FAQs, and related pages.
- Common mistakes: Catches ALL errors; Use ISNA for just #N/A
- Pair this function with comparison guides when another Excel formula might fit the same task better.
- Review fix-excel-formula-errors when unexpected errors appear after upgrading Excel or sharing across locales.