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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
16 toolsThe most-searched category on DevTools Hub — URL encoding, decoding, and Base64 conversions.
JWT
8 toolsThe single biggest source of search traffic — decoding claims, checking expiration, and JWT security.
Docker
5 toolsValidate, lint, and visualize Docker Compose files — and make sense of container networking.
OpenAPI
5 toolsValidate, view, and convert OpenAPI/Swagger specs without leaving the browser.
Toolkits
Generators Toolkit
4 toolsIndependent tools for the test data every project eventually needs — unique IDs, strong passwords, placeholder text — plus a way to check the strength of a password you already have. All run entirely in your browser.
JSON Toolkit
10 toolsFormat, validate, diff, minify, convert, query, and schema-generate/validate JSON — ten tools for the format everything speaks. All run entirely in your browser.
Encoding Toolkit
16 toolsBase64, URL, HTML, hex, and ASCII encoding and decoding, plus query string and full URL parsing, building, inspection, Unicode analysis, and string-literal escaping — sixteen 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
8 toolsEverything for working with JSON Web Tokens, in one place — decode, understand, verify, build, and secure them. All eight tools run entirely in your browser; nothing you paste is ever sent anywhere.
Hashing Toolkit
8 toolsMD5, SHA, checksums, HMAC, and password hashing — eight tools for hashing text, verifying files, and signing messages. All run entirely in your browser.
Regex Toolkit
6 toolsBuild, test, visualize, debug, and escape for JavaScript regular expressions — six tools covering the whole regex workflow. All run entirely in your browser.
SQL Toolkit
6 toolsFormat, validate, minify, diff, index-advise, and explain SQL — six tools covering readability, correctness, schema changes, 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
5 toolsValidate, lint, format, and visualize Docker Compose files and Dockerfiles — five 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
7 toolsValidate, format, calculate resources, diff, explore relationships, and merge or compare Helm values for Kubernetes manifests — seven tools covering correctness, readability, and resource planning. All run entirely in your browser.
YAML Toolkit
2 toolsValidate and format YAML — syntax errors, duplicate keys, parser-version gotchas, and consistent indentation — schema-agnostic, for any YAML file. All run entirely in your browser.
AWS Toolkit
9 toolsParse and build ARNs, generate, review, simulate, and minify IAM policies, validate tag policies, look up Regions, and validate CloudFormation templates — nine tools for everyday AWS work. All run entirely in your browser.
GraphQL Toolkit
2 toolsFormat and validate GraphQL queries, mutations, and SDL schemas with the real reference parser. All run entirely in your browser.
Latest tools
AWS Tag Policy Validator
Validate an AWS Organizations tag policy's syntax, operators, and size.
IAM Policy Minifier
Minify an IAM policy and check it against AWS's real character limits.
IAM Policy Simulator
Test whether an action on a resource is allowed across one or more IAM policies.
ARN Generator
Build a correctly formatted AWS ARN for 23 common resource types.
Regex Escape
Escape special regex metacharacters so a literal string can be safely embedded in a pattern.
SQL Index Advisor
Suggest candidate indexes from a query's WHERE, JOIN, ORDER BY, and GROUP BY clauses — before you've run it.
Latest articles
View all postsHow Docker DNS Resolution Works
What Docker's embedded DNS server at 127.0.0.11 actually resolves, why the default bridge network gets none of it, how Compose aliases work, and how to reach the host machine itself from inside a container.
Common Docker Compose Networking Errors
Five networking-specific Compose mistakes verified against a real install: the network_mode/networks conflict, a ports: mapping that silently does nothing under host mode, an external network that isn't found for a subtle reason, and more.
Docker Bridge vs Host vs Overlay Networks
The five Docker network drivers compared: what isolation and DNS each one actually gives you, why overlay always requires Swarm mode even for standalone containers, and when macvlan or ipvlan is the right call.