Secure Token / API Key Generator
Generate cryptographically secure random tokens and UUIDs — hex, Base64, Base64URL, or UUID v4.
Also known as: API key generator, Random string generator, Secure random generator, UUID generator
How it works
- 1Choose a format: Hex, Base64, Base64URL, or UUID v4.
- 2For hex/Base64/Base64URL, adjust the length using the slider or presets.
- 3Copy the generated token, or click regenerate for a new one.
- 4Toggle "Generate multiple at once" for a bulk batch you can download as a .txt file.
Why use Secure Token / API Key Generator
True cryptographic randomness
Every token uses crypto.getRandomValues(), never Math.random(), for genuine unpredictability.
Four practical formats
Hex, Base64, Base64URL, and spec-compliant UUID v4 cover the formats most APIs and systems actually expect.
Adjustable entropy
Choose token length from 8 to 64 bytes, with the resulting bit-strength shown alongside every token.
RFC 4122-compliant UUIDs
Generated UUIDs correctly set the version and variant bits, not just a random-looking string in UUID shape.
Bulk generation with export
Generate up to 200 tokens at once and download them as a plain text file.
Nothing transmitted
Every token is generated locally and never sent anywhere before you use it.
Who uses Secure Token / API Key Generator
Generating an API key for a new service
Produce a genuinely random hex or Base64URL key for authenticating requests to a new API.
Creating a session secret
Generate a high-entropy secret for signing or encrypting session tokens.
Generating unique database identifiers
Produce spec-compliant UUID v4 values for primary keys or record identifiers.
Producing a password-reset or verification token
Generate a URL-safe Base64URL token suitable for embedding directly in a reset or verification link.
Generating test data in bulk
Produce a batch of tokens at once for seeding development or test environments.
Creating placeholder identifiers for prototyping
Quickly generate realistic-looking UUIDs while mocking up a data model or API response.
About Secure Token / API Key Generator
Not all "random" is equal. Math.random() is a fast, statistically-decent pseudorandom generator, but it's not cryptographically secure — its internal state can, in principle, be inferred from its output, which makes it a genuinely bad choice for anything meant to be unguessable, like an API key or session token. crypto.getRandomValues() is different: it's backed by the operating system's cryptographically secure random number source, the same class of randomness used to generate encryption keys.
This tool uses crypto.getRandomValues() exclusively, for every format it offers. Hex and Base64/Base64URL tokens are raw random bytes encoded for readability or URL-safety; UUID v4 follows RFC 4122's exact bit-layout requirements — setting the version nibble to 4 and the variant bits correctly — so every generated UUID is a spec-compliant identifier, not just a random-looking string shaped like one.
Format choice matters for where a token ends up: hex is a safe universal default for API keys; Base64URL avoids the +, /, and = characters that need escaping in a URL, making it the right choice for tokens embedded in links like password-reset or email-verification URLs; UUID v4 is built for uniqueness as an identifier, not secrecy — it shouldn't be used as a password or session secret despite looking similarly random.
Bulk generation produces up to 200 tokens at once, downloadable as a plain text file, for situations like seeding test data or provisioning a batch of API keys. Every token — single or bulk — is generated entirely in your browser and never transmitted anywhere before you copy or download it.
Secure Token / API Key Generator vs. other options
How Open Tools Library compares to desktop software and other online tools.
| Feature | Open Tools Library | Desktop software | Other online tools |
|---|---|---|---|
| Price | Free, unlimited | openssl rand (free, CLI) | Often uses weak randomness |
| Randomness source | crypto.getRandomValues() (CSPRNG) | OS CSPRNG | Often Math.random() — not secure |
| Token privacy | Never leaves your device | Stays local | Sometimes generated server-side |
| UUID spec compliance | RFC 4122 v4 verified | Compliant | Varies |
| Bulk generation | Up to 200, with .txt download | Requires scripting | Rarely included |
| Installation | None | Required (CLI) | None |
Pro tips
- For anything security-sensitive, 32 bytes (256 bits) is a solid default — it's effectively unguessable with current or foreseeable computing power.
- Prefer Base64URL over Base64 for tokens that will appear in a URL, since it avoids characters that otherwise need percent-encoding.
- A UUID v4 is designed for uniqueness, not secrecy — don't use one as a password, API key, or session secret.
- If you ever suspect a generated token was exposed (logged, committed to a repo, shared accidentally), regenerate a fresh one rather than continuing to use it.
Technical specs
- Entropy source
- crypto.getRandomValues() (CSPRNG)
- Formats
- Hex, Base64, Base64URL, UUID v4
- Adjustable length
- 8 to 64 bytes (hex/Base64/Base64URL)
- UUID version
- v4, RFC 4122 compliant
- Bulk generation
- Up to 200 tokens per batch
- Processing location
- 100% local, in your browser
Privacy & security
A generated token is often destined to become a real secret — an API key or session token — so it should never pass through a server on its way to you.
Every token is generated entirely locally, using the browser's cryptographically secure random number generator.
Nothing is transmitted or logged, whether you generate one token or a bulk batch of 200.
No account, no email, no login — just a format and length in, tokens out.
The same local-only trust model applies whether you're generating a throwaway test value or a real production secret.
Frequently asked questions
Is this actually cryptographically secure?
Yes — every token uses crypto.getRandomValues(), the browser's cryptographically secure random number generator, never Math.random().
What's the difference between the formats?
Hex and Base64 are general-purpose encodings of random bytes; Base64URL is Base64 made safe for URLs; UUID v4 is a fixed-format 128-bit identifier following RFC 4122.
Is a UUID safe to use as a secret?
No — UUIDs are designed for uniqueness as identifiers, not secrecy. Use a hex or Base64URL token instead for anything that needs to stay secret.
Is a server involved in generating these?
No — every token is generated entirely in your browser using the Web Crypto API, with nothing transmitted anywhere.
How much entropy do I actually need?
32 bytes (256 bits) is a strong, future-proof default for security-sensitive tokens like API keys or session secrets; shorter lengths are fine for less sensitive uses like short-lived identifiers.
Troubleshooting
The token looks shorter than the byte length I set
Different formats encode the same number of bytes into different string lengths — hex uses 2 characters per byte, Base64/Base64URL use roughly 4 characters per 3 bytes, so a 32-byte token looks different in each format even though the underlying entropy is identical.
There's no length slider for UUID v4
That's by design — a UUID's format and length are fixed by the RFC 4122 specification and aren't adjustable.
Bulk generation is capped at 200
This is an intentional limit to keep the browser responsive — for larger batches, generate multiple rounds of 200.
Two tokens look similar at a glance
With enough entropy (32 bytes / 256 bits or more), a coincidental match or even a visually similar prefix is astronomically unlikely — a shared prefix is just a visual coincidence, not a sign of reduced randomness.
Related searches
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