Format, encode, decode, validate and generate common developer data directly in the browser where practical.
Format, minify and validate JSON in your browser.
Encode text to Base64 or decode Base64 to text.
Encode and decode URL components.
Generate random UUID v4 identifiers.
Generate SHA-256 hashes locally in your browser.
Test JavaScript regular expressions against text.
Decode JWT header and payload locally. Signature is not verified.
Encode or decode HTML entities.
Format or minify CSS.
These utilities are designed for quick inspection and transformation of text and data. JSON formatting, Base64, URL encoding, UUID generation, hashing, regex testing, JWT decoding, HTML entities and CSS formatting each have different security implications, so the individual pages explain what is and is not verified.
In particular, decoding a JWT does not verify its signature, and a hash does not encrypt data. Avoid pasting production secrets, private keys, access tokens or confidential customer information into tools unless you understand how the page processes them.
See Methodology & Accuracy for CalcNator's approach to local processing and external services.