Free Online JSON5 Validator & Checker
Sharing data between apps should be simple, clean, and easy for humans to read. JSON5 is a newer, easier version of standard JSON. It lets you write data quickly by using simple coding rules. Our Free Online JSON5 Validator is a quick tool that checks your data right away, finds errors, and helps you make sure your code is correct.
Whether you are setting up website tools, managing server files, or writing data that humans need to read, this tool helps you find and fix mistakes fast.
How to Check Your JSON5 Data
Checking your code for mistakes is very easy with our online tool:
- Paste Your Data: Type or paste your JSON5 code into the large text box.
- Upload a File: Or, click the Upload File button to bring a
.json5or.jsonfile straight from your computer. - Check for Errors: Click the blue Validate button to test your code and see any error messages instantly.
- Clear Everything: Click Clear to wipe the box clean and test a new piece of code.
🔒 100% Safe and Private: Your data and settings are completely secure. This tool checks your code inside your own web browser. No data is ever sent to our servers or stored online.
JSON vs. JSON5: Why You Need This Tool
Standard JSON is great for computers, but its strict rules make it hard for humans to write by hand. JSON5 fixes this problem. It allows you to write data the same way you write simple JavaScript.
Regular JSON tools will break if you try to use JSON5 features. That is why you need a special checker. Here is a simple look at what makes JSON5 much easier to use:
| Feature | Standard JSON (Old) | JSON5 (New & Easy) |
| Code Comments | ❌ Not allowed at all | Allowed! Use // for single lines or /* */ for blocks. |
| Object Keys | ❌ Must use double quotes (" ") | Can be plain words without any quotes. |
| Using Quotes | ❌ Double quotes only | You can use single quotes (' ') too. |
| Extra Commas | ❌ Breaks your code if you leave one at the end | Allowed at the end of lists and groups. |
| Long Text | ❌ Cannot split text across multiple lines | Allowed if you add a backslash (\) at the end of the line. |
| Numbers | ❌ Basic numbers only | Supports extra formats like Infinity, NaN, or leading plus signs. |
What to Do Next: Clean Your Data for Production
JSON5 is amazing when you are writing configuration files by hand. However, many live websites and apps still require the old, strict JSON format to work properly.
Once you use our tool to make sure your JSON5 data has no errors, you can copy it into our JSON Formatter. This helpful tool will instantly clean it up, remove your comments, add the required quotes, and give you fast, standard JSON that is ready for your website.
Frequently Asked Questions (FAQs)
What is JSON5?
JSON5 is an easy-to-read version of the standard JSON format. It adds simple rules from JavaScript to make it much easier for humans to write and manage data files.
Why does my code editor show errors when I use JSON5?
Most code editors think all data files must follow the strict, old JSON rules. To fix this, make sure your file ends with the .json5 extension or change your editor settings to support JSON5.
Can this tool show me exactly where my mistake is?
Yes. If you miss a bracket, forget a comma, or make a typo, the checker will tell you the exact line number so you can find and fix it quickly.
Does this work with old JSON files?
Yes! Every standard JSON file is already a valid JSON5 file. You can paste old JSON files here, and they will pass the check perfectly.
Do you save the files I upload?
No. The file upload button reads the text directly inside your web browser. Your files are never uploaded to the internet or seen by anyone else.