Magic Box
Paste anything — we detect the format and open the right tool.Paste anything — JSON, HTML, curl, JWT, CSV, regex — we detect it instantly and show you the right tool. We learn your patterns and suggest workflows automatically.
Pro Tip: Save Your Work
Click the save icon in any tool to keep important snippets. History auto-saves for 90 days, but saved items never expire.
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About Spoold
Spoold is a free, privacy-first developer toolbox for instant results without sign-ups. Format and validate JSON, convert YAML and TOML, preview HTML and Markdown, decode and sign JWTs, convert curl to fetch or axios, browse OpenAPI and Swagger specs with curl, inspect TLS certificates, run a multi-language code editor, estimate LLM tokens, build Mermaid diagrams, hash and encode data, and use 72+ tools—all in the browser for supported workflows.
Paste into the Magic Box and Spoold detects JSON, HTML, JWT, curl, OpenAPI, Base64, CSV, regex, timestamps, and more—then suggests the best match. Heavy lifting runs client-side so your payloads stay on your device for those tools.
No account required. Save and share via encrypted links when you want to collaborate. Spoold stays ad-free through optional support and lightweight in-layout promotions for its own tools. For categories, privacy details, and FAQs, read the About page.
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