Fydler UtilityBelt - UUID Decoder

UUID Decoder

Text & Development Tool

UUID

UUID Versions

v1: Time-based — includes timestamp and MAC address
v4: Random — most common, purely random
v6: Reordered time-based — similar to v1 but sortable
v7: Unix time-based — time-ordered with random suffix

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lucide.createIcons(); const input = document.getElementById('ud-input'); const output = document.getElementById('ud-output'); function decodeUUID(uuid) { const cleaned = uuid.replace(/[^0-9a-fA-F]/g, ''); if (cleaned.length !== 32) return { error: 'Invalid UUID: must be 32 hex digits.' }; const hex = cleaned.toLowerCase(); const version = parseInt(hex[12], 16); const variantBits = parseInt(hex[16], 16); let variant; if ((variantBits & 0x8) === 0) variant = 'Reserved (NCS backward compatible)'; else if ((variantBits & 0xC) === 0x8) variant = 'RFC 9562 / RFC 4122'; else if ((variantBits & 0xE) === 0xC) variant = 'Reserved (Microsoft GUID)'; else variant = 'Reserved (future)'; const timeHex = hex.substring(0, 12) + hex.substring(14, 16) + hex.substring(16, 20) + hex.substring(20, 24); const timeInt = parseInt(timeHex, 16); const nodeHex = hex.substring(20, 24) + ':' + hex.substring(24, 28) + ':' + hex.substring(28, 32); const nodeBytes = hex.substring(20, 32); const formatted = hex.substring(0,8) + '-' + hex.substring(8,12) + '-' + hex.substring(12,16) + '-' + hex.substring(16,20) + '-' + hex.substring(20,32); let html = '

'; html += `

UUID: ${formatted}

`; html += `

Version: ${version}

`; html += `

Variant: ${variant}

`; if (version === 1) { const ts = (timeInt - 0x01b21dd213814000) / 10000; const date = new Date(ts); html += `

Timestamp: ${date.toUTCString()}

`; const clockSeq = ((parseInt(hex[16], 16) & 0x3F) << 8) | parseInt(hex[18] + hex[19], 16); html += `

Clock Sequence: ${clockSeq}

`; html += `

Node (MAC): ${nodeHex.toUpperCase()}

`; } if (version === 2) { html += `

Note: DCE Security UUID — limited decoding available.

`; } if (version === 6) { const ts = (timeInt - 0x01b21dd213814000) / 10000; const date = new Date(ts); html += `

Timestamp: ${date.toUTCString()}

`; } if (version === 7) { const tsMs = timeInt >>> 16; const date = new Date(tsMs); html += `

Timestamp: ${date.toUTCString()} (${tsMs} ms)

`; const randA = parseInt(hex.substring(16, 20), 16); const randB = hex.substring(20, 32); html += `

Random: ${randA.toString(16).padStart(4,'0')}-${randB}

`; } if (version === 8) { html += `

Note: Custom/vendor-specific UUID format.

`; } html += '

'; return { html }; } function update() { const val = input.value.trim(); if (!val) { output.innerHTML = ''; return; } const result = decodeUUID(val); if (result.error) { output.innerHTML = `

${result.error}

`; } else { output.innerHTML = result.html; } } input.addEventListener('input', update); function showToast(msg) { const toast = document.getElementById('toast'); const toastMsg = document.getElementById('toast-message'); toastMsg.textContent = msg; toast.classList.add('show'); setTimeout(() => toast.classList.remove('show'), 2000); }