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.

Όλα τα εργαλεία（45）

Beautify, minify and validate JSON in your browser.

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Base64 Encode / Decode

Encode or decode Base64 text locally.

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URL Encode / Decode

Percent-encode or decode URL components.

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

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Generate UUID v4 identifiers in bulk.

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Password Generator

Create strong random passwords offline.

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Generate random hex or alphanumeric strings.

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Convert between Unix time and human-readable dates.

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Decode JWT header and payload without sending tokens away.

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Test regular expressions with live matches.

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Encode or decode HTML special characters.

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Query String Parser

Parse URL query strings to JSON and back.

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Convert CSV tables to JSON objects and back.

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Beautify or minify XML in your browser.

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Break down a 5-field cron expression.

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Color Converter

Convert between HEX and RGB color formats.

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Number Base Converter

Convert numbers between binary, octal, decimal and hex.

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

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Beautify SQL locally with dialect-aware formatting.

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Parse and format TOML, convert to JSON locally.

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Compare two JSON documents and highlight structural differences.

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JSONPath Tester

Evaluate JSONPath queries against JSON in your browser.

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JSON Schema Tool

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

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

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Timezone Converter

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

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Date Calculator

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

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

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Minify JavaScript, CSS, HTML or JSON locally.

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

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Generate or verify bcrypt hashes offline with bcryptjs.

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

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Compress or decompress text with browser CompressionStream (gzip).

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robots.txt Generator

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

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

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Compose Content-Security-Policy directives for your site.

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llms.txt Generator

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

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Schema Markup Generator

Generate common JSON-LD schema.org snippets locally.

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

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chmod Calculator

Convert between symbolic and octal Unix file modes.

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Generate RSA key pairs in the browser with Web Crypto.

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

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htpasswd Generator

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

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

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

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

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Συχνές ερωτήσεις

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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