Free online developer tools
Developers search for specific jobs: pretty-print JSON before a PR, decode a JWT from a staging cookie, bulk-generate UUIDs for fixtures, or turn a Python dict into strict JSON for an API doc. This hub groups those utilities in one place so you can bookmark one index and deep-link to the exact tool when you need it.
Most of these handle the awkward cases other formatters reject. The JSON formatter accepts trailing commas, comments, and single-quoted keys instead of failing on the first error. The Python dict converter understands True, False, None, and single quotes. The JWT decoder shows header and payload claims without asking you to paste a token into a server you do not control.
Every listing below runs primarily in your browser on WebToolz365: no accounts, no paywall on core features, and no server round-trip for the sensitive paths. Use the JSON formatter for RFC-style validation, the Python dict converter when samples use single quotes and True/False/None, and the JWT decoder when you only need claims—not another npm install.
Each tool page links back to the others it pairs with, so you can chain steps without returning here: format a JSON payload, diff it against yesterday’s, then hash the result. Bookmark this page as your index, or bookmark the individual tool you reach for most.
Tools in this category
- UUID GeneratorCreate unique IDs instantly for apps, forms, and automation.Open tool →
- JSON Formatter & BeautifierClean up messy JSON and validate it in one click.Open tool →
- Python Dict ConverterConvert Python dict and JSON both ways quickly.Open tool →
- Base64 Encoder DecoderEncode or decode Base64 text for APIs and configs.Open tool →
- Base64 to Image ConverterDecode Base64 image strings and download the image file.Open tool →
- Image to Base64 ConverterConvert PNG/JPG/WebP files into Base64 strings instantly.Open tool →
- Hash GeneratorGenerate SHA hashes in-browser for checks and verification.Open tool →
- QR Code GeneratorTurn links and text into custom QR codes.Open tool →
- JWT DecoderDecode JWT payload details for quick token checks.Open tool →
- Markdown PreviewWrite Markdown and preview rendered output instantly.Open tool →
- JSON CompareStructural diff for JSON documents.Open tool →
- Cron Expression BuilderBuild cron schedules and copy valid expressions.Open tool →
- Regex TesterTest regex patterns live with flags and match highlights.Open tool →
- SQL FormatterFormat SQL for readability or minify for compact output.Open tool →
- CSV to JSON ConverterConvert CSV to JSON and JSON back to CSV.Open tool →
Frequently asked questions
- Are these developer tools free?
- Yes. WebToolz365 developer tools are free to use. Core processing runs in your browser for privacy; no payment is required to use the features described on each tool page.
- Do I need an account?
- No account is required. Open a tool, paste or upload where supported, and copy the result.
- Which tool should I use for JSON cleanup?
- Use the JSON formatter & beautifier for indent/minify/validate. If your snippet is Python-style (single quotes, True/False/None), use the Python dict to JSON converter instead.