o1 via the ApexApi gateway
OpenAI's first reasoning model, which thinks before answering rather than streaming an immediate reply. Later o-series releases deliver the same approach far more cheaply. Call it through ApexApi's unified, OpenAI-compatible API with one `ak-` key, alongside every other model in the catalog. It supports a 200,000-token context window, tool / function calling, image (vision) input, and streaming responses. Pricing is $18.00 input and $72.00 output per 1M tokens, billed pay-per-use from your credit balance with no subscription.
o1 is served through ApexApi's unified, OpenAI-compatible API. One key, one format, with smart routing and automatic failover. Provider: OpenAI.
Why o1
200,000-token context
Reason over long documents, codebases, and multi-turn history in a single request.
Tool & function calling
Structured outputs and tool orchestration for agentic and automation workloads.
Vision input
Send images alongside text for document, UI, and visual-understanding tasks.
Specifications
- Modality
- chat
- Context window
- 200K tokens
- Max output
- 100K tokens
- Streaming
- Yes
- Tool / function calling
- Yes
- Vision input
- Yes
o1: measured reliability
From real calls ApexApi made to o1 during health sweeps over the last 30 days. Our own measurements, not vendor claims.
- Success rate
- 100%
- Avg latency
- 4.2s
- Calls measured
- 1
- Last checked
- Aug 30
See how o1 compares against every model we serve on the model rankings.
o1 pricing
- A million tokens in and a million out costs $90.00 here, all-in.
- For lighter work, GPT-OSS 20B from the same maker costs 200× less — one string apart on the same key.
Getting started with o1
OpenAI-compatible. Point your client at ApexApi, swap your key, and call it. No new SDK to learn.
from openai import OpenAI
client = OpenAI(
base_url="https://api.apexapi.dev/v1",
api_key="<YOUR_APEXAPI_KEY>",
)
response = client.chat.completions.create(
model="openai/o1",
messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)o1 use cases
What teams build with o1 on ApexApi.
Agents & automation
Tool-using agents that orchestrate multi-step workflows and call APIs.
Coding assistants
Code generation, refactoring, reviews, and multi-file reasoning.
RAG & knowledge apps
Summarization and long-document Q&A grounded in your own data.
o1 vs other models
How it compares, and on ApexApi you can switch between any of them with a single string change, same key, same endpoint.
o1 vs Claude Opus 4.7
Compare o1 against this model on price, capabilities, and latency. A/B them with a single key on ApexApi.
Learn more about Claude Opus 4.7 API →o1 vs GPT-5.5
Compare o1 against this model on price, capabilities, and latency. A/B them with a single key on ApexApi.
Learn more about GPT-5.5 API →o1 vs Gemini 3.1 Pro Preview
Compare o1 against this model on price, capabilities, and latency. A/B them with a single key on ApexApi.
Learn more about Gemini 3.1 Pro Preview API →o1 API: FAQ
How do I call o1 through ApexApi?
Create an ApexApi key, point your client at https://api.apexapi.dev/v1, and POST to /v1/chat/completions with the model set to `openai/o1`. The API is OpenAI-compatible, so an existing OpenAI SDK works once you change the base URL and key.
How much does o1 cost on ApexApi?
$18.00 per million input tokens and $72.00 per million output tokens, all-in with no separate platform fee. You buy credits and pay per call, with no subscription or minimum.
What is the context window for o1?
200,000 tokens. It can return up to 100,000 tokens in a single response.
Does o1 support tool calling and image input?
o1 supports tool / function calling, image (vision) input, and streaming responses.
What should I use instead of o1?
From the same maker, GPT-5.6 Sol costs less for lighter work. Switching is one string: it runs on the same endpoint and the same key, so there is nothing to re-integrate.
Ready to build with o1?
One API key. Every major AI model. Pay only for what you use.
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