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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.
Password Security
6 toolsGenerate a strong password, check how one holds up, and set or validate the policy your team follows.
Docker
7 toolsValidate, lint, and visualize Docker Compose files — and make sense of container networking.
Regex
6 toolsBuild, test, visualize, and debug regular expressions — with a cheat sheet when you need a quick reference.
Toolkits
Generators Toolkit
3 toolsIndependent tools for the test data every project eventually needs — unique IDs and placeholder text. 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
10 toolsMD5, SHA, checksums, HMAC, and password hashing — ten 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
7 toolsValidate, lint, format, visualize, merge, and resolve Docker Compose files, and lint Dockerfiles — seven 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
5 toolsValidate, diff, resolve, and convert .env files — five 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
10 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.
Algorithms Toolkit
8 toolsComputer science fundamentals for practicing engineers — algorithm complexity, performance analysis, and scalability, with interactive tools and practical examples. All run entirely in your browser.
Data Structures Toolkit
4 toolsHow the structures underneath every algorithm actually work — arrays, hash tables, trees, and more, visualized step by step. All run entirely in your browser.
Scalability Toolkit
3 toolsThe numbers behind systems that hold up under load — caching, capacity, and the metrics worth actually tracking. All run entirely in your browser.
Distributed Systems Toolkit
2 toolsTools for the problems that show up once a system spans more than one machine — unique IDs, coordination, and consistency. All run entirely in your browser.
Password Security Toolkit
6 toolsGenerate a strong password, check the strength of one you already have or estimate one hypothetically, define or validate the policy an organization follows, and grade its storage practices. All run entirely in your browser.
Encryption Toolkit
2 toolsEncrypt and decrypt text with AES, and generate RSA key pairs — entirely in your browser using the native Web Crypto API.
Latest tools
RSA Key Pair Generator
Generate a real RSA public/private key pair as PEM — for signing (RS256) or encryption (OAEP).
AES Encrypt/Decrypt
Encrypt or decrypt text with AES-GCM or AES-CBC, using a key derived from a passphrase.
Environment Variable Resolver
Expand ${VAR} references between variables in the same .env-style set, chained across hops.
Compose Config Inspector
Resolve ${VAR} interpolation and expand shorthand fields, like docker compose config.
Docker Compose Merge Visualizer
See exactly what -f base.yml -f override.yml produces, and which file set each field.
S3 Bucket Policy Generator
Build an S3 bucket policy — public read, CloudFront OAC, cross-account, or custom.
Latest articles
View all postsEncoding vs Encryption vs Hashing
All three turn one piece of data into another, which is exactly why they get confused — and why mixing them up in real code is a security mistake, not just a vocabulary slip. Encoding is reversible with no key (Base64), encryption is reversible only with the right key (AES, RSA, TLS), and hashing is never reversible at all (bcrypt, Argon2). What each is actually for, and the real mistakes that come from picking the wrong one: "encoding" a secret as if it were hidden, storing passwords encrypted instead of hashed, and assuming HTTPS protects data once it's already stored.
AES vs RSA
Asking whether AES or RSA is "better" is like asking whether a hammer beats a screwdriver — one is symmetric (one key, both directions), the other asymmetric (a public/private pair), and that difference decides which one can even do the job. Why RSA can't encrypt more than a couple hundred bytes at a time, why AES has no way to give someone an encrypt-only capability, the hybrid-encryption pattern every real system (TLS included) actually uses, and why RSA-4096 isn't "stronger than AES-256" no matter how the numbers look.
What Happens If Password Hashes Leak?
A leaked hash table isn't a leaked password table, but it isn't nothing either. What actually happens depends first on how the passwords were stored (plaintext, a fast hash, or a real password-hashing algorithm), then on what an attacker does with a stolen table (crack the easy ones first, then feed the confirmed pairs into credential stuffing against completely unrelated sites), and finally on what the breached organization does in response — including why a strong hash doesn't mean skipping the forced reset.