UUID / Hash / Base64 / URL Encode
Four daily dev tools in one: bulk UUID v4, SHA-256/1/512 hash, Base64 encode/decode (URL-safe option), URL encode. Web Crypto API standard.
Generated via crypto.randomUUID() — standard UUID v4, cryptographically secure.
Four tools in one
- 🔑 UUID v4: generate 1-100 at once, optional UPPERCASE and dash-stripped (for databases that dislike special chars)
- #️⃣ Hash: SHA-256 / SHA-1 / SHA-512 — live as you type
- 🔐 Base64: UTF-8 encode/decode (full Vietnamese support), URL-safe option
- 🔗 URL Encode: for query strings and form data
Why no MD5?
MD5 was deprecated in the 2010s due to collision attacks — no longer safe for passwords or signatures. Web Crypto API doesn't expose it for that reason. Default to SHA-256.
Who this is for
Backend devs, API integrators, anyone debugging JSON/YAML/CSV payloads or working with structured data.
FAQ
Is my sensitive data safe?
Yes. JSON/YAML/CSV you paste is NOT uploaded to any server. All processing happens locally in your browser.
Is there a size limit?
Browser RAM dependent. Files under 10MB run smoothly. Larger files may freeze the tab.
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