Developer tools

Local developer utilities: JSON/YAML/XML/SQL, Base64, JWT, hash, Prettier, CSP/llms.txt, Mermaid and more. Everything runs in your browser on LocalKit—no upload for computation.

About this category

Audience: Front-end, back-end, DevOps and security engineers who want private, on-device helpers.
Limits: Not a production secrets vault or remote HTTP auditor; limited by browser memory.
Privacy: Tools run locally in your browser. Hosted on Cloudflare Pages—no third-party content-processing API.

Všechny nástroje（45）

Beautify, minify and validate JSON in your browser.

Base64 Encode / Decode

Encode or decode Base64 text locally.

URL Encode / Decode

Percent-encode or decode URL components.

MD5, SHA-1, SHA-256 and more — computed locally.

Generate UUID v4 identifiers in bulk.

Password Generator

Create strong random passwords offline.

Generate random hex or alphanumeric strings.

Convert between Unix time and human-readable dates.

Decode JWT header and payload without sending tokens away.

Test regular expressions with live matches.

Encode or decode HTML special characters.

Query String Parser

Parse URL query strings to JSON and back.

Convert CSV tables to JSON objects and back.

Beautify or minify XML in your browser.

Break down a 5-field cron expression.

Color Converter

Convert between HEX and RGB color formats.

Number Base Converter

Convert numbers between binary, octal, decimal and hex.

Format, minify, validate YAML and convert YAML ↔ JSON in your browser.

Beautify SQL locally with dialect-aware formatting.

Parse and format TOML, convert to JSON locally.

Compare two JSON documents and highlight structural differences.

JSONPath Tester

Evaluate JSONPath queries against JSON in your browser.

JSON Schema Tool

Validate JSON against a schema or generate a draft schema from samples.

Generate TypeScript, Go, Python, or other type definitions from JSON.

Timezone Converter

Convert a date and time across time zones without leaving the browser.

Date Calculator

Add or subtract days and compute the difference between two dates.

Format JS, HTML, CSS and more with self-hosted Prettier.

Minify JavaScript, CSS, HTML or JSON locally.

Encrypt and decrypt text with Web Crypto (AES-GCM) locally.

Generate or verify bcrypt hashes offline with bcryptjs.

Convert among hex, Base64, URL encoding and UTF-8 byte views.

Compress or decompress text with browser CompressionStream (gzip).

robots.txt Generator

Build a robots.txt draft with Allow/Disallow and sitemap lines.

Draft Access-Control-* response headers for API testing notes.

Compose Content-Security-Policy directives for your site.

llms.txt Generator

Draft llms.txt / llms-full.txt files for AI crawlers and GEO.

Schema Markup Generator

Generate common JSON-LD schema.org snippets locally.

Build and explain five-field cron expressions with friendly controls.

chmod Calculator

Convert between symbolic and octal Unix file modes.

Generate RSA key pairs in the browser with Web Crypto.

Generate TOTP codes from a secret (RFC 6238) offline.

htpasswd Generator

Create Apache htpasswd lines (bcrypt / MD5 / SHA) locally.

Generate box-shadow, gradient, radius and flex snippets with live preview.

Edit and render Mermaid diagrams locally (self-hosted Mermaid).

Parse, preview and convert CSV with Papa Parse in your browser.

FAQ

Do these tools upload my data?

No. Tools in this LocalKit category run locally in your browser—nothing is uploaded to www.908885.com for computation.

Who is this for?

Front-end, back-end, DevOps and security engineers who want private, on-device helpers.

Any limits?

Not a production secrets vault or remote HTTP auditor; limited by browser memory.

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