medium severity

How to Fix: JSON Parse Error

Your code expects JSON but receives malformed or non-JSON data, causing parse errors.

json parse errorunexpected token jsoninvalid jsonmalformed json response

Symptoms

'Unexpected token' error in console

'JSON.parse' failure

Response looks like JSON but isn't valid

Common Causes

01

Server returning HTML error page instead of JSON

02

Trailing comma in JSON

03

Unescaped special characters

04

UTF-8 BOM in response

The DevConsole Solution

DevConsole shows raw response bodies and automatically validates JSON. Instantly see what's wrong with the response.

Step-by-Step Fix

1

View Raw Response

See exactly what the server sent, before parsing.

2

Validate JSON

Use the built-in JSON validator to find syntax errors.

3

Check Content-Type

Verify the response header says 'application/json'.

Frequently Asked Questions

Why am I getting HTML instead of JSON?

Often means the server threw an error and returned its default error page. Check for 500 errors.

How do I handle non-JSON responses gracefully?

Check Content-Type header before parsing, and wrap JSON.parse in try-catch.

Stop debugging blindly

DevConsole gives you the visibility and control to fix issues like json parse error in seconds, not hours.

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