How to Get an OpenRouter API Key for Free and Use Its Free Models

In short: OpenRouter is one API that reaches hundreds of models from many providers. Some of them are free: every model whose ID ends in :free. A free OpenRouter account can send 50 requests a day to those models, 20 a minute, without buying anything. In October 2026 there are 17 free text models, including Google's Gemma 4. OpenRouter's API follows OpenAI's format, so the key works in most apps made for OpenAI.

What you need

• An account on openrouter.ai (click Sign in at the top right).
• A computer. Windows, Mac or Linux all work.
• Nothing to pay for 50 free requests a day. OpenRouter's limits page raises that to 1,000 a day once an account has bought at least 10 credits in total.

Step 1: Find the free models

Open Models at the top of openrouter.ai. In the left column, drag Prompt pricing to FREE (box 1). Every model left in the list has (free) in its name (box 2) and costs $0 per million tokens.

Click a model to see its ID - the name you send in a request, such as google/gemma-4-31b-it:free. The :free at the end is what makes the request free; the same model without it is the paid version.

Step 2: Open the API Keys page

An API key is a password that lets a program use your account. Open openrouter.ai/settings/keys - it opens API Keys in your workspace settings - and click New Key (box 1).

Step 3: Create your free API key

Fill in the window:

1. Name - anything you will recognise, such as "my laptop".
2. Expiration - when the key stops working.
3. Credit limit - the most this key may spend. For free models only, the smallest limit is the safest: free requests cost nothing, and a limit stops the key spending credits by accident if you ever add some.
4. Click Create, then copy the key.

Keep the key private:

• Anyone who has your key can use your account.
• Never paste it into a website, a public code repository or a screenshot.
• If it leaks, delete it on the API Keys page (the menu at the end of its row) and create a new one.

Step 4: Allow the free providers (privacy settings)

Free models are served by providers with their own data policies, and OpenRouter only sends your request to providers your settings allow. Open openrouter.ai/settings/privacy and scroll to Data Training:

1. Allow free endpoints that train on request data - providers serving free models that may keep your prompts and replies or train on them.
2. Allow free endpoints that publish prompts - providers that may publish prompts and replies to public datasets.

With a switch off, OpenRouter excludes those providers from routing, so a free model served only by them will not answer. With it on, assume anything you send can be kept, used for training or, for the second switch, made public. Do not send private or confidential information to free models.

Step 5: Check your free limits

The free limits are set by how many credits your account has ever bought, not by the model:

Three more rules from OpenRouter's limits page:

• More accounts or API keys do not raise your limits.
• The daily count runs on the UTC day.
• If your balance goes below zero, even free models return a 402 error until you add credits.

To see how many free requests you have left today, open this address with your key (Step 6 shows how to send it): https://openrouter.ai/api/v1/key. The free_model_daily_requests part of the answer shows used, limit and remaining - for a new account, {"used":0,"limit":50,"remaining":50}.

Step 6: Send your first request (no programming)

Open a command window. On Windows, press the Start key, type PowerShell and open it. On a Mac, open Terminal.

Windows (PowerShell) - paste these lines, putting your key in place of YOUR_API_KEY:

$env:OPENROUTER_API_KEY = "YOUR_API_KEY"
$body = '{"model":"poolside/laguna-s-2.1:free","messages":[{"role":"user","content":"Explain how AI works in a few words"}]}'
$r = Invoke-RestMethod -Method Post -Uri "https://openrouter.ai/api/v1/chat/completions" -Headers @{ Authorization = "Bearer $env:OPENROUTER_API_KEY" } -ContentType "application/json" -Body $body
$r.choices[0].message.content

Mac or Linux (Terminal):

export OPENROUTER_API_KEY="YOUR_API_KEY"
curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "poolside/laguna-s-2.1:free",
    "messages": [{"role": "user", "content": "Explain how AI works in a few words"}]
  }'

You get a short answer back. That is one request from your 50 for the day.

Free models fail now and then: a busy provider returns 429, and a provider that is down returns 404 with Provider returned error. If a free model fails, just change the model name and try again.

Or let OpenRouter choose: use the model ID openrouter/free instead of a model name. OpenRouter then picks an available free model for each request, so a busy or broken model is skipped for you. Each request still counts toward your 50 a day.

Step 7: Use it in an app made for OpenAI

In any app that asks for an OpenAI key, change three settings:

Python's openai library works the same way:

import os
from openai import OpenAI

client = OpenAI(base_url="https://openrouter.ai/api/v1", api_key=os.environ["OPENROUTER_API_KEY"])
reply = client.chat.completions.create(
    model="poolside/laguna-s-2.1:free",
    messages=[{"role": "user", "content": "Explain how AI works in a few words"}],
)
print(reply.choices[0].message.content)

The free models list

These are the 17 free text-output models in OpenRouter's public model list in October 2026. The list changes often; the models page always shows the current one.

When something goes wrong

Words to know

• API key: the password that identifies you to the API and counts your usage. See what is an API key.
• :free model: a free variant of a model on OpenRouter, with the limits above.
• Credits: OpenRouter's prepaid balance, used by paid models.
• Provider: the company whose servers run the model; OpenRouter passes your request to one.
• Token: a piece of a word; the unit models read and write. See tokens and context windows.

More free AI API keys

OpenRouter is one of the providers with a free tier. How to get AI API keys for free lists each one with its daily limit and source. For higher daily limits on one provider's models, see how to get a Groq API key for free (1,000 requests a day) and how to get a Gemini API key for free.