OpenAI o4-mini
openai-o4-miniOpenAI's o4-mini reasoning model. A cost-efficient reasoning model that trades some depth for much lower price and latency, good for high-volume math and code tasks.
- Price · 1M in / out
- US$1.32 / US$5.28
- Context
- 200,000 tokens
- Max. output
- 100,000 tokens
- Input → output
- Text + Image → Text
- Developer
- OpenAI
- Updated
- 23 September 2026
The provider is phasing this model out.
Playground
Try OpenAI o4-mini
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This run
at most US$0.0055 · 0.55 credits reserved
Billed by the tokens actually used; the unused part of the reservation is refunded.
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10 free credits (US$0.10) when you sign up with Google
Usable 24 hours after sign-up, up to 5 runs per day and at most 2 credits per run. Other sign-in methods start without credits. Enough for 18 runs of this model.
About OpenAI o4-mini
OpenAI o4-mini is a model by OpenAI in the Text & chat category. On Railwail, OpenAI o4-mini costs US$1.32 per 1M input tokens and US$5.28 per 1M output tokens. The context window holds 200,000 tokens, and one response can be up to 100,000 tokens long.
Pricing
| Input | US$1.32 / 1M tokens |
|---|---|
| Output | US$5.28 / 1M tokens |
- Billed by the tokens each request actually uses.
- 1 credit = US$0.01
Cost calculator
Price calculator
Total
US$0.40
40 credits
Per request
US$0.004 · 0.4 credits
Each request is rounded up to 0.01 credits.
API
curl https://railwail.com/api/v1/chat/completions \
-H "Authorization: Bearer $RAILWAIL_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "openai-o4-mini",
"messages": [
{
"role": "user",
"content": "Explain what a vector database is in two sentences."
}
],
"max_tokens": 1024
}'import os
from openai import OpenAI
client = OpenAI(
api_key=os.environ["RAILWAIL_API_KEY"],
base_url="https://railwail.com/api/v1",
)
completion = client.chat.completions.create(
model="openai-o4-mini",
messages=[
{
"role": "user",
"content": "Explain what a vector database is in two sentences.",
},
],
max_tokens=1024,
)
print(completion.choices[0].message.content)import OpenAI from "openai";
const client = new OpenAI({
apiKey: process.env.RAILWAIL_API_KEY,
baseURL: "https://railwail.com/api/v1",
});
const completion = await client.chat.completions.create({
model: "openai-o4-mini",
messages: [
{
role: "user",
content: "Explain what a vector database is in two sentences."
}
],
max_tokens: 1024
});
console.log(completion.choices[0].message.content);// npm install railwail
import railwail from "railwail";
const rw = railwail(process.env.RAILWAIL_API_KEY);
const res = await rw.chat("openai-o4-mini", [
{ role: "user", content: "Explain what a vector database is in two sentences." },
], { max_tokens: 1024 });
console.log(res.choices[0].message.content);Specifications
- Model ID
openai-o4-mini- Developer
- OpenAI
- Category
- Text & chat
- Input
- Text, Image
- Output
- Text
- Context window
- 200,000 tokens
- Max. output
- 100,000 tokens
- Billing
- By usage (tokens or GPU time)
- Lifecycle
- Deprecated
- Catalog entry updated
- 23 September 2026
Tags
- openai
- o-series
- reasoning
- cost-efficient
Use cases
Frequently asked questions
What is OpenAI o4-mini?
OpenAI o4-mini is a model by OpenAI in the Text & chat category. On Railwail you can call it with an API key through the Railwail API.
How much does OpenAI o4-mini cost on Railwail?
On Railwail, OpenAI o4-mini costs US$1.32 per 1M input tokens and US$5.28 per 1M output tokens. You are charged for what each request actually uses. Usage is paid from prepaid credits; 1 credit equals US$0.01.
What is the context window of OpenAI o4-mini?
The context window of OpenAI o4-mini holds 200,000 tokens. One response can be up to 100,000 tokens long.
How fast is OpenAI o4-mini?
There are not enough measured runs of OpenAI o4-mini on Railwail yet to state a run time. It depends on the input, the settings and the load at the provider.
Is OpenAI o4-mini better than Claude Fable 5.1?
That depends on the task. OpenAI o4-mini (OpenAI) and Claude Fable 5.1 (Anthropic) are both models in the Text & chat category. The comparison page shows their prices and specifications side by side.
Compare OpenAI o4-mini and Claude Fable 5.1Can OpenAI o4-mini process images?
Yes. OpenAI o4-mini accepts images as input in addition to text.
How do I use OpenAI o4-mini through the API?
Create a Railwail API key and send your request with the model ID openai-o4-mini. Code examples for curl, Python and JavaScript are in the API section of this page.
Comparable models
All in this category- Claude Fable 5.1Anthropic
Anthropic's model for the most demanding reasoning and long-horizon agentic work. 1M-token context window, up to 128K output tokens, adaptive thinking that is always on.
- Claude Opus 4.8Anthropic
The most capable model of Anthropic's Opus 4 series. State of the art on long-horizon agentic work, coding and knowledge tasks, with a 1M-token context window at standard pricing.
- Claude Opus 5.5Anthropic
Anthropic's current Opus model for long-running agentic coding and knowledge work. 1M-token context window, up to 128K output tokens, adaptive thinking that is always on.
Use OpenAI o4-mini via the API
One API key for every model on Railwail. Usage is charged from prepaid credits, 1 credit = US$0.01.