Gemini API 400 (INVALID_ARGUMENT / FAILED_PRECONDITION)

Is there an outage right now?

Gemini API / AI Studio official status is operational. If this error persists, it is likely an implementation or environment issue on your side.

View Gemini API / AI Studio status

What this error means

400 means the request is invalid: a bad parameter, a malformed body, an invalid API key, or—as FAILED_PRECONDITION—billing not enabled or the free tier not available in your region.

Common causes

  • Invalid or out-of-range parameter (e.g. an unsupported generationConfig value)
  • Malformed request body or wrong field names
  • Invalid API key, or a key restricted to other APIs
  • FAILED_PRECONDITION: billing not enabled, or free tier unavailable in your region
  • Unsupported file type / inline data too large

How to fix

  1. 1.Read the error detail—it identifies the bad field
  2. 2.Validate the request body and parameter ranges
  3. 3.Check the API key is valid and allowed to call the Generative Language API
  4. 4.Enable billing, or use a supported region
  5. 5.Verify file MIME types and size limits

When waiting helps (and when it won't)

Request/config error—waiting will not help. Fix the parameter, key, or billing/region named in the detail.

Alternatives when Gemini API / AI Studio is down

OpenAI APIClaude APIMistral APIGroq API

Related errors

FAQ

What is 400 INVALID_ARGUMENT?

400 means the request is invalid: a bad parameter, a malformed body, an invalid API key, or—as FAILED_PRECONDITION—billing not enabled or the free tier not available in your region.

How do I fix 400 INVALID_ARGUMENT?

Read the error detail—it identifies the bad field / Validate the request body and parameter ranges / Check the API key is valid and allowed to call the Generative Language API / Enable billing, or use a supported region / Verify file MIME types and size limits