Free access token generator

Mock access tokens for development and testing

Generate realistic API keys, Bearer tokens, hex secrets and mock JWTs for your dev environment, API tests and documentation. Choose the format, prefix and length, then copy or download the set. Everything runs 100% in your browser — no sign-up, no server, nothing stored.

tokentonic // token works 100% in your browser

Token format

API key and Bearer styles look like real provider keys; mock JWT builds a real header.payload.signature structure.

Key length

Length applies to the random body, not the prefix. Mock JWT uses a fixed structure instead.

Prefix

Prefixes identify the key type at a glance — the convention real APIs use (sk- for secret keys, ak- for access keys).

Number of tokens

Generate a handful for a test suite, or one-offs for screenshots and docs.

Your mock tokens will appear here. Click any token to copy it individually.

Honest limits — read before you use these

These are MOCK tokens for development and testing only. They are random strings with no connection to any account, API or service.
They grant access to NOTHING. A real API key is issued and validated by the provider's servers; these strings exist only in your browser and will be rejected by every real API.
Never use these in production or as real secrets. Never commit them to git, paste them into production configs, or treat them as real credentials — and develop the same hygiene for mock tokens as real ones.
Safe uses: testing auth middleware, seeding dev/staging databases, API documentation examples, screenshots and tutorials, CI pipeline fixtures.

How the token works runs

No accounts, no network calls, no fine print. The whole tool is a small JavaScript file that runs on your device.

Cryptographically secure randomness

Every character is drawn with crypto.getRandomValues(), the browser's built-in secure random number generator, with rejection sampling to avoid modulo bias. The output line shows the entropy in bits for each token.

Real-world formats

API-key style with sk- / ak- / tok- prefixes, Bearer-style tokens, hex secrets, base64url strings, and mock JWTs with a genuine header.payload.signature structure (unsigned, labeled mock).

Nothing leaves your device

Generation, copying and the .txt download all happen locally in your browser tab. There is no backend, no database and no analytics watching what you generate. Close the tab and the tokens are gone.

Where mock tokens earn their keep

This tool exists for one honest job: realistic-looking tokens that carry no access. Here is where that is genuinely useful — and where it is not.

Use it

Testing auth code

Building login middleware, an API gateway or a key-rotation flow? Generate tokens and walk through validation, expiry and revocation logic with data shaped like the real thing.

Use it

Docs and screenshots

Writing API documentation or a tutorial with curl examples? Drop in a generated token instead of typing a fake key by hand — and never screenshot a real one.

Never

Production secrets

Mock tokens must never ship. Production keys come from the provider's dashboard or your secrets manager, are stored in environment variables, and are rotated on a schedule. See our security practices guide.

New to access tokens?

Learn what access tokens actually are, how Bearer authentication works, and how API keys differ from OAuth tokens.

Read the guide

Quick answers

What is an access token generator? +

An access token generator creates random strings shaped like real API credentials — API keys, Bearer tokens, hex secrets or JWTs. TokenTonic makes mock tokens for development and testing: they look like the real thing but grant access to nothing and are tied to no account.

Can I use these tokens with a real API? +

No. Real APIs validate tokens against their own servers; only keys issued by the provider work there. These tokens are random strings generated in your browser — every real API will reject them.

What is the difference between an API key and a Bearer token? +

An API key is usually a long-lived secret sent in a header like x-api-key; a Bearer token is sent as Authorization: Bearer <token> and is often short-lived, issued via OAuth 2.0. Our access tokens guide explains both in depth.

What does the mock JWT contain? +

A genuine three-part structure — header.payload.signature — with an unsigned HS256 header, a payload containing a mock subject and timestamp, and 32 random bytes as the signature. The payload is labeled mock, and the token will fail any real signature check, which is exactly the point.

How much entropy do the tokens have? +

Each output line shows the bits of entropy. A 32-character hex token carries 128 bits; 32 base64url characters carry 192 bits. The formats guide has the full math.

Is the generator really private? +

Yes. It is plain JavaScript running in your browser using crypto.getRandomValues(). It sends nothing over the network, sets no cookies and stores nothing. See our privacy page for the full details.

Access token guides

Short, practical explainers on tokens: what they are, which formats exist, where mock tokens are useful, and how to handle the real ones safely.

Guide