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Visualize AI prompt chain JSON as a vertical flowchart.

Parse and pretty-print SSE stream chunks from OpenAI and similar APIs.

Parse and visualize AI API SSE streaming responses.

Visualize how AI models split text into tokens with color coding.

Interactive guide and template generator for writing accessible image alt text.

Searchable reference for all WAI-ARIA roles with descriptions, required properties, and allowed states.

Detect browser name, version, OS, and check support for key web APIs.

Simulate how colors or images appear to people with color blindness.

Parse and display all accessible cookies for the current page.

Upload and view CSV files as a formatted table.

Display navigator properties: user agent, platform, language, hardware concurrency, and more.

Parse, edit, and export .env files in a key-value table.

Searchable reference of all HTTP status codes with descriptions.

Click any pixel in an uploaded image to get its HEX, RGB, and HSL color values.

Upload an image and compare its file size as JPEG, PNG, and WebP side by side to pick the best format.

Detect the true format of any image file by reading its magic bytes — catches misnamed files instantly.

View file info and basic EXIF metadata from uploaded images.

Instantly check an image's dimensions, file size, format, and megapixels.

Upload and view JSON files with pretty-printing and structure info.

Browse mock API endpoint patterns and copy sample JSON responses for /users, /posts, /todos, and more.

Visualize JSON as an interactive collapsible tree structure.

Browse, add, edit, and delete localStorage entries for the current origin.

Live Markdown editor with side-by-side HTML preview.

Browse and copy Material Design color palette hex values.

Searchable reference of common MIME types grouped by category.

Preview how your page looks when shared on Facebook and LinkedIn.

Reference table of PayPal sandbox test card numbers with one-click copy.

View title, author, page count, creation date, and other PDF metadata.

Real-time collaborative estimation for agile teams. Create a room, share the link, pick cards, reveal together.

Searchable reference of well-known TCP/UDP port numbers and their services.

Preview how an image scales across mobile, tablet, laptop, and desktop viewport widths.

Real-time collaborative retrospective board for agile teams. Add cards, vote, discuss, create action items.

View window size, screen resolution, pixel ratio, and active breakpoint in real time.

Reference table of image dimensions for every major social media platform.

Reference table of all Stripe test card numbers with one-click copy.

Upload and view any text file with line numbers and file info.

Preview your Twitter/X card in summary and large-image formats.

Generate a unique URL to capture and inspect incoming HTTP requests in real time.