21 developer tools · free, no sign-up
Free Online Developer Tools
Use these free online developer tools to inspect structured data, format code, test expressions and prepare text for another system. Start with the input type: JSON, XML, YAML, SQL, HTML or an encoded string. Then choose whether you need validation, readable formatting, smaller output or a conversion between representations.
Formatters & Validators
8 toolsMinifiers & Optimization
3 toolsData Conversion
2 toolsEncoders & Security
2 toolsTesting & Utilities
6 toolsQuestions and answers
Developer Tools FAQs
Does formatting JSON make it valid?
Not necessarily. Formatting changes presentation; validation checks syntax. Even valid JSON can contain values or fields that do not satisfy your application’s requirements.
When should I minify code?
Minify a reviewed build output when smaller transfer size is useful. Keep readable source for maintenance and test the generated result before publishing it.
Can a SQL formatter execute my query?
A formatter rearranges SQL text for readability. It does not execute a query against your database or establish that the query returns the intended data.
How should I test a regular expression?
Include inputs that should match, inputs that should fail and relevant edge cases. Check the regex engine and flags because behavior can differ between programming environments.
Is Base64 encoding a way to protect a secret?
No. Base64 is a reversible representation of bytes, not encryption. Anyone who can read the encoded text can generally decode it without a key.
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