TypeError: X is not a function
This error matches known, documented patterns with reliable solutions.
Quick Fix (Most Common Solution)
- Check the import statement
- Verify the function exists in the module
Seeing "TypeError: X is not a function"? This error can be frustrating, but it's usually fixable. It typically affects your development workflow or system. Below you'll find clear, step-by-step solutions to resolve this issue.
What This Error Means
You tried to call something as a function that is not actually a function.
Frequently documented in developer and vendor support forums.
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Common Causes
- Wrong import/export syntax
- Undefined variable called as function
- Incorrect destructuring
How to Fix
- Check the import statement
- Verify the function exists in the module
- Log the value before calling it
Last reviewed: March 2026 How we review solutions
Optional follow-up
Some users ask whether saving fixes for recurring errors would be useful when the same issue appears again.
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Frequently Asked Questions
Why is my import undefined?
The module might use default export while you are using named import.
How do I debug this?
Console.log the value before calling to see its actual type.
Related Resources
Also Known As
- Node.js error
- Node runtime error
- JavaScript server error
- Node exception
Common Search Variations
- "node js error fix"
- "node command not working"
- "node app crashing"
- "javascript server error solution"
- "node runtime crash fix"
- "how to debug node error"
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