GPT-4.1 Mini
GPT-4.1 Mini is a mid-sized model delivering performance competitive with GPT-4o at substantially lower latency and cost. It retains a 1 million token context window and scores 45.1% on hard instruction evals, 35.8% on MultiChallenge, and 84.1% on IFEval. Mini also shows strong coding ability (e.g., 31.6% on Aider’s polyglot diff benchmark) and vision understanding, making it suitable for interactive applications with tight performance constraints.
Specifications
Modalities
Supported Parameters
Max Output Tokens
32,768Data policy
- Prompt retention
- May be retained
- Training
- Not used for training
Whether a provider trains on prompts is a declared value from our terms with them. Retention is determined from the upstream listing for every host this model can reach. Neither is guessed.
Measured performance
- Routed across 2 independent backends
Measured through FastMetal's own gateway over the last 30 days (661 first-response samples).
Throughput is sampled once a day: the median of 27 observations over the last 30 days.
Time to first response is measured to the first streamed chunk; throughput counts all output tokens, including reasoning tokens. These are observations, not a performance guarantee.
Code Examples
curl https://api.fastmetal.ai/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer YOUR_API_KEY" \
-d '{
"model": "gpt-4.1-mini",
"messages": [{"role": "user", "content": "Hello!"}]
}'How GPT-4.1 Mini actually answers
Real responses to our standard prompts, recorded on FastMetal.
Count the number of 'r's in 'strawberry'
Count the number of 'r's in 'strawberry'. Explain your reasoning step by step.
Debug This Error
I'm getting the following error in my Node.js application: TypeError: Cannot read properties of undefined (reading 'map') at UserList (/app/components/UserList.js:12:25) at renderWithHooks (/app/node_modules/rea…
Code Review
Please review the following Python function and suggest improvements for readability, performance, and best practices: def get_data(url, retries=3): import requests import time for i in range(retries):…
Frequently asked questions
- How much does the GPT-4.1 Mini API cost?
- On FastMetal, GPT-4.1 Mini is billed per token: $0.44 per 1M input tokens and $1.76 per 1M output tokens on a US-dollar account, before tax. Usage is drawn from a prepaid balance; there is no subscription or monthly fee.
- Can I call GPT-4.1 Mini with the OpenAI SDK?
- Yes. Point base_url at https://api.fastmetal.ai/v1 and pass "gpt-4.1-mini" as the model; existing OpenAI-style code works unchanged, including streaming, tool calls and structured output.
- What is the context window of GPT-4.1 Mini?
- 1,047,576 tokens, shared between the prompt and the response.
- What do I need to try GPT-4.1 Mini?
- Create an account and add credit; the model is then available both in the browser chat and over the API. There is no contract or minimum spend.
Try GPT-4.1 Mini right now
GPT-4.1 Mini is available on FastMetal through one API key. Start in the browser, or call it from the OpenAI SDK.