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// a sandbox of 139 sharp tools

Every little generator
you keep googling for.

QR, barcodes, bcrypt hashes for PHP, UUIDs, JWT decoders, color palettes — fast, local, no signup. Search the sandbox and start.

Card / Luhn Validator

Security · tool

Card / Luhn Validator

Validate credit-card numbers and detect brand.

Luhn check

✓ Valid

Brand

Visa

Digits

16

Validates with the Luhn algorithm. Test numbers only — never paste real card data.

// about the sandbox

The small utilities you need,
without the ad-walls.

Every generator runs entirely in your browser. Your inputs never leave the page — no servers, no logging, no tracking pixels. Open the tool, get the thing, close the tab.

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  • 139sharp tools
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