JavaScript Error Messages
The language of the web, in browsers and server runtimes.All JavaScript pages
- TypeError: Cannot read properties of undefined (reading 'x')JavaScript throws this TypeError when it reads a property of a value that is undefined. Find which object is missing, then guard it with ?. or a default.
- TypeError: x is not a function (JavaScript)JavaScript throws x is not a function when you call a value that is undefined, an object or a string: a typo, a missing import, or .map on a non-array. Fixes.
- Uncaught RangeError: Maximum call stack size exceededRangeError: Maximum call stack size exceeded means a function recursed without end, often a missing base case or a getter reading itself. Add the exit case.
- Uncaught ReferenceError: x is not definedReferenceError: x is not defined means no reachable scope declares that name. Declare it with let or const, fix the typo, or load the script first. Real output.