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UUID generators, JSON formatters, JWT decoders and more — fast, free, and 100% private. Every tool runs locally in your browser; your data never touches a server.
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Popular categories
Encoding
11 toolsThe most-searched category on DevTools Hub — URL encoding, decoding, and Base64 conversions.
JWT
6 toolsThe single biggest source of search traffic — decoding claims, checking expiration, and JWT security.
SQL
4 toolsValidating and formatting SQL syntax across Postgres, MySQL, and more.
Regex
5 toolsTesting and building JavaScript regular expressions without leaving the browser.
Toolkits
Generators Toolkit
3 toolsThree independent generators for the test data every project eventually needs — unique IDs, strong passwords, and placeholder text. All run entirely in your browser.
JSON Toolkit
6 toolsFormat, validate, diff, minify, and convert JSON — six tools for the format everything speaks. All run entirely in your browser.
Encoding Toolkit
11 toolsBase64, URL, and HTML encoding and decoding, plus query string and full URL parsing, building, and inspection — eleven tools for the encodings that show up constantly in web development. All run entirely in your browser.
Date & Time Toolkit
5 toolsTimestamps, timezones, and cron schedules — five tools for the two date-and-time problems every backend eventually runs into. All run entirely in your browser.
JWT Toolkit
6 toolsEverything for working with JSON Web Tokens, in one place — decode, understand, verify, and build them. All six tools run entirely in your browser; nothing you paste is ever sent anywhere.
Hashing Toolkit
5 toolsMD5, SHA, checksums, and HMAC — five tools for hashing text, verifying files, and signing messages. All run entirely in your browser.
Regex Toolkit
5 toolsBuild, test, visualize, and debug JavaScript regular expressions — five tools covering the whole regex workflow. All run entirely in your browser.
SQL Toolkit
4 toolsFormat, validate, minify SQL, and find the real bottleneck in a query plan — four tools covering readability, correctness, and performance. All run entirely in your browser.
OpenAPI Toolkit
5 toolsView, validate, diff, and put an OpenAPI/Swagger document to work — five tools covering the full spec lifecycle. All run entirely in your browser.
Docker Toolkit
4 toolsValidate, lint, format, and visualize Docker Compose files and Dockerfiles — four tools covering the whole Docker workflow. All run entirely in your browser.
GitHub Actions Toolkit
4 toolsValidate, visualize, lint, and audit secrets in GitHub Actions workflows — four tools covering correctness and security. All run entirely in your browser.
Environment Toolkit
4 toolsValidate, diff, and convert .env files — four tools for the dotenv format's real parsing rules and the gotchas that fail silently. All run entirely in your browser.
Kubernetes Toolkit
4 toolsValidate, format, calculate resources, and diff Kubernetes manifests — four tools covering correctness, readability, and resource planning. All run entirely in your browser.
Latest tools
URL Inspector
Parse a URL, audit its encoding, and surface phishing and redirect red flags.
Query Parameter Builder
Build a query string from key/value rows or a JSON object.
URL Builder
Visually build a URL from protocol, host, path, query params, and fragment.
URL Parser
Break a URL down into protocol, host, port, path, query, and fragment.
Query String Parser
Break a URL's query string into individual parameters, or export as JSON.
K8s Diff
Compare two Kubernetes manifests field-by-field, matched by resource identity, with server-managed noise stripped by default.
Latest articles
View all postsWhat Is JWT Authentication?
How JWT-based authentication actually works end-to-end: the login-to-request flow, access vs. refresh tokens, where to store them client-side, what the server checks on every request, and how it differs from session auth and OAuth2.
Kubernetes Resource Requests vs Limits
Why requests and limits are read by two entirely different parts of Kubernetes, what overcommitment actually means, the precise (and very different) consequences of exceeding a CPU limit versus a memory limit, and namespace-wide guardrails.
Kubernetes YAML Explained
The declarative model behind kubectl apply, the four fields every manifest needs, why you'll rarely write a bare Pod, labels vs annotations, multi-document files, and why apiVersion isn't just a version number.