JWT Expiry Checker & Decoder
Inspect, decode, and verify JSON Web Tokens (JWT) locally. Features real-time countdown timers, header/payload analysis, and signature validation.
FOCUSED WEB UTILITIES
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The toolbox
27 toolsMCP Config Builder
Visual configuration generator and schema validator for Claude Desktop, Cursor, Windsurf, and ChatGPT Model Context Protocol files.
JSON to GraphQL SDL Converter
Transform JSON payloads into clean, schema-compliant GraphQL SDL types. Supports scalar detection, nested objects, and list field inference.
Bluesky Grapheme Counter
Validate AT Protocol post limits (300 graphemes, 3000 bytes) with accurate emoji counting (`Intl.Segmenter`) and auto-thread splitting.
Aspect Ratio & Image Resizer
Calculate proportions with Euclid's GCD algorithm. Crop and resize images on canvas with safe-zone overlays for TikTok, Shorts, and IG Reels.
AI Text Markdown Formatter
Instantly strip markdown syntax (`**`, `#`, `>`, code blocks) from ChatGPT, Claude, and Gemini outputs for clean copy-pasting to Slack or docs.
Real-Time Caption Cleaner
18-step copy refiner: strips hidden zero-width characters, normalizes smart quotes, audits duplicate hashtags, and injects platform line breaks.
DIY Calculator Hub
Calculate spacing, layouts and material quantities for board and batten, fence pickets, balusters, gravel and stone projects.
WCAG Color Contrast Evaluator
Analyze color combinations against WCAG 2.1 AA (4.5:1) and AAA (7:1) contrast standards. Real-time relative luminance calculations.
BakersMath Sourdough Calculator
Precise baker's percentages, levain water/flour isolation, and hydration math. Scale recipes easily for single or multi-loaf bakes.
HandwriteLabs Signature Generator
Convert typed text to natural cursive handwriting, or draw digital signatures on canvas for instant vector PDF downloads.
JSON to CSV Converter
Flatten nested JSON arrays into clean CSV spreadsheets compatible with Excel and Google Sheets entirely in browser memory.
United States
ParkWatch Campground Finder
Compare national park campgrounds, reservation rules, fees, equipment limits and public campsite availability snapshots.
United States
ZipSocio Demographic Explorer
Explore US Census ACS data across ZIP codes: compare household income, home values, education metrics, and population density.
United States
Pharma Transparency Tool
Search public financial relationships between healthcare providers and manufacturers, including consulting payments and research funding.
United States
AssemblyCheck VIN & Deduction Checker
Look up a vehicle's final assembly location by VIN and explore car-loan interest deduction estimates and eligibility information.
Clay Shrinkage Ruler & Pottery Calc
Generate printable PDF/SVG shrinkage rulers, convert wet-to-fired pottery dimensions, and compute studio kiln costs.
United States
Subsurface Atlas
Enter a U.S. address to explore the USDA soil map unit at that point, including components, horizons, drainage, hydrologic group, hydric rating, and Ksat.
France
Vérif Attestation
Pre-check a French employer attestation for missing information, SIRET errors and inconsistent contract dates before transmission to France Travail.
Brazil
Lucro Delivery
Estimate restaurant margins, food costs and menu prices for iFood delivery in Brazil, and compare delivery plans.
Australia · QLD & NSW
Tenancy Notice Date Calculator
Work out tenancy notice dates for Queensland and New South Wales using your role, tenancy type, reason and service method.
Argentina
Monotributo Claro
Explore Argentina’s Monotributo categories, recategorization and related Ingresos Brutos pathways with dated sources.
South Africa
UIF Toolkit
Estimate South African UIF contributions, benefits, credit days and payouts, with multilingual explanations and source notes.
General-purposeAccount required · Uses credits
Omnishelf
Save public posts, links and uploads in a private, searchable library of places, recipes, products and ideas.
Workflow-specificAccount required · Uses credits
DevBuildTool Agents
Run focused AI reviews for contractor compliance and certified payroll, with confirmed rules and source evidence for human review.
General-purpose
SubliStudio
Find compatible sublimation ink, blanks and press-setting references, or build a setup for mugs, tumblers and apparel.
Android · ESP32
Waterline
Monitor household tank level bands with an ESP32 detector and Android app, with cloud readings, nearby Bluetooth controls and configurable alarms.
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Open a tool directly. Each guide explains the workflow, account requirements and practical limits.
Know where your data goes.
Most calculations run in your browser. Tools that query public services identify their sources and explain what is sent.
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From Web Crypto and JSON schemas to color contrast and soil data, our technical articles explain the details behind the output.
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