API keys · Guide

How to get a free Mistral API key

A free Mistral API key comes with Mistral’s Free mode, which turns on API access with no credit card. Here’s how to create one in the Mistral console, what Free mode means for limits and your data, and how to keep the key safe.

Cost: Free mode
Card needed: No (Free mode)
Shown: Once, at creation
Key format: Not documented

Steps

Get your key

Sign up or sign in at the Mistral console. New accounts are asked to name their organisation; Mistral creates the organisation and a default workspace for you.
Open API Keys in the left sidebar and click Create new key.
Set a name, an expiration date and the connector access scope, then click Create new key again. You can’t change a key’s workspace, scope or expiry later.
Copy the key straight away: Mistral shows the full key only once, and you can’t retrieve it after closing the dialog. Store it in a password manager or secrets vault.
Paste it into the box on this page to check it works and see which models it can use.

Source: Mistral’s Activate and generate an API key quickstart.

Test your key

Your key goes from your browser straight to Mistral AI, never to this site, and isn’t saved. Checking several keys or providers? Use the API key checker.

Free mode

What Free mode includes

Mistral says Free mode is the default for new accounts: “API access is enabled by default with no credit card required. Usage and rate limits apply.” Turning on pay-as-you-go billing moves you to higher limits.

Limits: Mistral sets limits per model in requests per second, tokens per minute and tokens per month. It doesn’t publish Free mode numbers; yours are on the limits page in the admin console. Free mode has the lowest limits.
Paid tiers go up with what you’ve been billed: Tier 1 when pay-as-you-go is on, then Tier 2 above €20 or $20, Tier 3 above €100 and Tier 4 above €500. Mistral says prepaid credits don’t raise your tier.
Your data: in Free mode, Mistral says it may use your inputs and outputs to train its models. You can opt out in the admin panel’s Privacy settings (the “Anonymous improvement data” toggle).
One inconsistency: one of Mistral’s organisation-setup pages says team members can’t generate working keys until billing is active. If a new key fails, check the billing page in the console.
Where it runs: api.mistral.ai is the global endpoint. Mistral also offers EU and US endpoints, at a regional upcharge.

Use it

Call the API with your key

Save the key as an environment variable called MISTRAL_API_KEY; Mistral’s Python and TypeScript SDKs read it. Send it in the Authorization header:

Terminal

curl https://api.mistral.ai/v1/chat/completions \
  -H "Authorization: Bearer $MISTRAL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "mistral-small-latest",
    "messages": [{"role": "user", "content": "Hello, Mistral!"}]
  }'

This is the example from Mistral’s quickstart, unchanged. Per-token prices for Mistral’s models are compared on our Mistral API pricing page.

Security

Keep your key safe

Set an expiration date on every key and rotate keys regularly; organisations can enforce an expiry policy.
Store keys in a password manager or secrets vault. Mistral says: “Do not share it or commit it to version control.”
Use one workspace per environment (development, production), so a leaked test key can’t touch production.
Keep the official SDK up to date: Mistral’s advisory MAI-2026-002 says mistralai 2.4.6 on PyPI and @mistralai/mistralai 2.2.2 to 2.2.4 on npm were compromised in May 2026. If you installed those versions, rotate your keys.

FAQ

Frequently asked questions

Is the Mistral API free?

Yes, in Free mode, which Mistral says is the default for new accounts: API access is on with no credit card required, and usage and rate limits apply. Mistral doesn’t publish the Free mode limits; they’re shown in the admin console. Turning on pay-as-you-go raises your limits as your billed usage grows.

Do I need a phone number or credit card for a Mistral API key?

Mistral’s current docs say Free mode needs no credit card. Its API-key setup docs don’t list phone verification as a step, though some third-party guides describe an SMS check, so have a phone to hand. One organisation-setup page still says keys need active billing, so check billing if a new key fails.

Does Mistral use my API data for training?

In Free mode, Mistral says it may use your inputs and outputs to train its models. You can opt out in the admin panel under Privacy, with the “Anonymous improvement data” toggle. Don’t send confidential data until you’ve checked that setting.

Can I see my Mistral API key again?

No. Mistral shows the full key only once, in the dialog after you create it, and you can’t retrieve it after closing that dialog. If you lose it, delete it in the console and create a new one. You also can’t change a key’s workspace, scope or expiry after creating it.

Why does my Mistral key return a 401 error?

Mistral’s error glossary says a 401 means the key is missing, invalid or expired, or belongs to a different workspace. Its API answers with a short body such as “Invalid API Key”. Check you copied the whole key, that it hasn’t expired, and that you’re using it with the right workspace.

What does a Mistral API key look like?

Mistral doesn’t document a key format, so the checker on this page never rejects a Mistral key because of how it looks. It sends the key only to api.mistral.ai, straight from your browser, and reports exactly what Mistral answers.