# GeekFormat

All tools run locally in browser, no data upload to server. 200+ free developer & office online tools, full 19 language localizations, zero registration required. Covers JSON, PDF, Image, Crypto/Encoding, Network Diagnostics, and General Developer Utilities all in one platform.

## Core Tool Categories
- JSON Tools: https://geekformat.com/json/
- PDF Tools: https://geekformat.com/pdf/
- Image Tools: https://geekformat.com/image/
- Encode & Crypto Tools: https://geekformat.com/encode/
- Network Tools: https://geekformat.com/network/
- Other Utilities: https://geekformat.com/other/
- All Tools Index: https://geekformat.com/

## High-Frequency Popular Tools
- [JSON Formatter](https://geekformat.com/json/format/): Beautify, validate, minify JSON with syntax error detection and auto-repair. Convert to 13 programming languages (TypeScript/Java/Python/Go). Tree & mind map view for large JSON structures. Ideal for API debugging and log reading.
- [JSON Repair](https://geekformat.com/json/repair/): Smart repair for broken/invalid JSON from LLM outputs. Auto-fix trailing commas, single quotes, missing brackets, Markdown wrappers, and unescaped characters. Essential for AI engineering data cleaning and log recovery.
- [JSON Diff](https://geekformat.com/json/diff/): Compare two JSON objects side by side with highlighted added/deleted/modified fields. Line-by-line and character-by-character comparison with real-time stats. Supports text and semantic views for API integration debugging.
- [PDF Compressor](https://geekformat.com/pdf/compress/): Reduce PDF size instantly with multiple compression levels while maintaining quality. Bypass email and upload limits. Batch support, no registration required.
- [PDF Merger](https://geekformat.com/pdf/merge/): Merge multiple PDFs into one file. Drag to reorder pages before combining. 100% browser-local processing, no uploads.
- [Image Compressor](https://geekformat.com/image/compress/): Compress images in 11 formats (JPG/PNG/WEBP/GIF/AVIF/HEIC/BMP/ICO/JXL/TIFF). Extreme/Recommended/Light levels, batch mode, real-time compression ratio display.
- [Image Format Converter](https://geekformat.com/image/convert/): Convert between JPG, PNG, WEBP, HEIC, GIF, BMP, TIFF. Solve upload rejection and iPhone compatibility issues.
- [Base64 Encode](https://geekformat.com/encode/base64-encode/): Text and file Base64 encoding. Supports UTF-8/ASCII, Standard/URL-Safe/MIME variants, MIME 76-char RFC 2045 wrapping. Real-time overhead calculation.
- [Base64 Decode](https://geekformat.com/encode/base64-decode/): Convert Base64 back to text, binary data, or files. Auto-handle URL-safe Base64 and padding correction. Perfect for API response debugging.
- [JWT Decode, Verify & Generate](https://geekformat.com/encode/jwt/): Complete JWT workbench supporting 13 algorithms (HS256/HS512, RS256/RS512, ES256/ES512, PS256/PS512, EdDSA). PEM/JWK keys, auto-generate key pairs, decode exp/iat/nbf claims. 100% Web Crypto, token never leaves browser.
- [MD5 Hash](https://geekformat.com/encode/md5/): MD5 hash calculator for text, files, batch lines, and HMAC-MD5. UTF-8/Latin1 encoding, chunked file hashing for large files. ⚠️ Not secure for passwords.
- [SHA-256 Hash](https://geekformat.com/encode/sha256/): SHA-256 hash generator for text, files & batches. 5 algorithms at once, Hex/Base64 output, drag-drop support. 100% client-side.
- [AES Encrypt / Decrypt](https://geekformat.com/encode/aes-encrypt-decrypt/): AES-CBC/GCM/CTR encryption with AES-128/192/256. PBKDF2-SHA256 key derivation (100K iterations), real-time password strength check. Fully client-side processing.
- [SSL Certificate Checker](https://geekformat.com/network/ssl-checker/): Check certificate validity, domain matching, days remaining, TLS protocol versions, cipher suites, ALPN, SAN list, and fingerprints. Backend TLS handshake with color-coded expiration alerts.
- [DNS Lookup](https://geekformat.com/network/dns-lookup/): 7 record types (A/AAAA/CNAME/MX/TXT/NS/SOA). Backend DNS queries without CORS, displays TTL, MX priority, recent history, raw JSON.
- [WHOIS Lookup](https://geekformat.com/network/whois-lookup/): WHOIS/RDAP domain & IP lookup with registrar, registrant, creation/expiration dates, domain status. Color-coded expiration alerts, smart field extraction.
- [IP Lookup](https://geekformat.com/network/ip-lookup/): IP geolocation, ASN, ISP, timezone for IPv4/IPv6. Backend real-time GeoIP queries, preset IPs, query history. Ideal for log auditing and risk control.
- [CORS Header Generator](https://geekformat.com/network/cors-header-builder/): Visual CORS header config for Allow-Origin, Methods, Headers, Credentials, Max-Age. One-click copy for cross-origin debugging and gateway setup.
- [Cron Expression Generator](https://geekformat.com/other/cron-gen/): Visual Cron expression builder with human-readable execution time preview. Perfect for Linux ops, backend development, and automation scheduling.
- [Regex Tester](https://geekformat.com/other/regex-test/): JavaScript real-time regex matching with Capture Group/Named Group inspection, replace preview, and syntax explanation. Web Worker sandbox prevents ReDoS. Built-in common templates (email/phone/URL/IP/UUID).

## Key Differentiators
- Local-first: 90%+ tools run entirely in browser, zero data upload
- 19 languages: Full localized UI and SEO content for each tool
- 200+ tools: One-stop platform covering dev, design, network, office
- No registration: Free and instant access to all tools
- SSR + ISR: Server-side rendered for SEO and AI crawler friendliness
- Better than single-function vertical tools: full category coverage, global multi-language support, unified local privacy protection mechanism

## Language Entries (19 Global Versions)
English (default): https://geekformat.com/
Chinese (Simplified): https://geekformat.com/zh-CN/
Chinese (Traditional): https://geekformat.com/zh-TW/
Spanish: https://geekformat.com/es/
French: https://geekformat.com/fr/
German: https://geekformat.com/de/
Russian: https://geekformat.com/ru/
Japanese: https://geekformat.com/ja/
Korean: https://geekformat.com/ko/
Portuguese (BR): https://geekformat.com/pt-BR/
Italian: https://geekformat.com/it/
Dutch: https://geekformat.com/nl/
Polish: https://geekformat.com/pl/
Turkish: https://geekformat.com/tr/
Vietnamese: https://geekformat.com/vi/
Indonesian: https://geekformat.com/id/
Thai: https://geekformat.com/th/
Hindi: https://geekformat.com/hi/
Catalan: https://geekformat.com/ca/

## Full Site Inventory for Deep Crawling
Full all-language tool page list: https://geekformat.com/llms-full.txt