JSON & Data
Format, validate, compare, and convert structured data.
- JSON Formatter
- JSON Diff
- JSON ↔ YAML
- JSON ↔ CSV
- SQL Formatter
KitLumi · A brighter browser toolkit
Small tools.
Bright ideas.
Fast, focused utilities for everyday technical work. No account, no setup, and no upload when a tool is marked Local Only.
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41tools process entirely locally
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Most used tools
Twelve popular entry points cover structured data, encoding, text, identifiers, images, and PDFs.
Live
JSON Formatter
Format, validate, sort, and minify JSON with exact error locations.
LiveJSON Diff
Compare parsed JSON values and list structural changes by path.
LiveBase64
Convert text or files to and from Base64.
LiveURL Encoder
Encode or decode URL components and inspect query parameters.
LiveHash Generator
Calculate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 together.
LiveRegex Tester
Test regular expressions with matches and capture groups.
LiveTimestamp Converter
Convert Unix timestamps and human-readable dates.
LiveUUID Generator
Generate one or many standards-based UUIDs.
LivePassword Generator
Create strong passwords with clear entropy controls.
LiveImage Compressor
Reduce image size while controlling output quality.
LiveImage Converter
Convert PNG, JPEG, WebP, and supported AVIF images locally.
LivePDF Merge
Combine PDF files and arrange pages before export.
Start from the job
Browse by task
Use familiar actions when you know the job but not the exact tool name.
Format & Validate
Clean structured data and catch syntax errors.
JSON Formatter · SQL Formatter · Line ToolsEncode & Decode
Transform text and data between common encodings.
Base64 · URL Encoder · HTML EntitiesConvert Data & Files
Change image, document, and data formats locally.
JSON ↔ YAML · Image Converter · PDF to ImagesGenerate
Create identifiers, secrets, codes, and test data.
UUID · ULID · PasswordCompare
Find structural and line-level changes between inputs.
JSON Diff · Text DiffInspect
Examine patterns, metadata, headers, and values.
Regex Tester · Image Metadata · IP LookupTool index
Categories
Forty-two working utilities, grouped by the data, file, or network task you are working with.
Encoding & Crypto
Encode values and calculate hashes in your browser.
- Base64
- URL Encoder
- Hash Generator
- JWT Decoder
- File Checksum
Image Tools
Compress, resize, convert, and inspect images locally.
- Image Compressor
- Image Resizer
- Image Converter
- HEIC Converter
- QR Scanner
PDF Tools
Merge, split, rotate, and extract PDF pages.
- PDF Merge
- PDF Split
- PDF Organizer
- PDF to Images
- Images to PDF
Text Tools
Count, compare, transform, and test text.
- Regex Tester
- Word Counter
- Text Diff
- Case Converter
- Markdown Preview
Date & Identifiers
Convert Unix time and generate browser-secure identifiers.
- Timestamp Converter
- UUID Generator
- Cron Generator
- ULID Generator
Generators
Generate passwords, UUIDs, and downloadable QR codes.
- Password Generator
- UUID Generator
- QR Code Generator
Network Tools
Inspect public IP data and calculate private IPv4 subnets.
- IP Lookup
- CIDR Subnet Calculator