Model detail
GPT-5.4 Pro
GPT-5.4 Pro is OpenAI's most advanced model, building on GPT-5.4's unified architecture with enhanced reasoning capabilities for complex, high-stakes tasks. It features a 1M+ token context window (922K input, 128K output) with support for text and image inputs. Optimized for step-by-step reasoning, instruction following, and accuracy, GPT-5.4 Pro excels at agentic coding, long-context workflows, and multi-step problem solving.
Model specs
- Model ID
-
gpt-5.4-pro
- Context length
- 1.05M
- Max output
- 128K
- I/O modalities
- Released
- 2026-03
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API endpoints
One MixRoute gateway, OpenAI-compatible
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OpenAI-compatible
/v1/chat/completionsPOST
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Tiered pricing
Unit: /1M Tokens
| Tier | Input /1M Tokens | Output /1M Tokens |
|---|---|---|
| standard Length ≤ 272K | $30.0000 | $180.0000 |
| long_context Length > 272K | $60.0000 | $270.0000 |
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Selection summary
Quickly judge whether it fits your workload
What is this model good for?
Pro model for complex professional work
GPT-5.4 Pro: GPT-5.4 Pro uses more compute to think harder and provide consistently better answers.. 1,050,000-token context.
What should you check before using it?
1,050,000 context, 128,000 output
OpenAI model. Supports tool calling, function calling. Knowledge cutoff: 2025-08-31.
Why use it through MixRoute?
Drop-in via OpenAI-compatible endpoint on MixRoute
Set the model parameter to "gpt-5.4-pro" and use your MixRoute API key.
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Capabilities & compatibility
Unconfirmed capabilities stay "Unknown," no guesses
Tool calling
GPT-5.4 Pro supports function and tool calls.
tools definition; the response returns tool_calls to execute and feed results back.
Streaming
GPT-5.4 Pro supports streamed responses.
stream: true streams tokens incrementally, so chat UIs render as they arrive.
Prompt caching
GPT-5.4 Pro supports prompt caching under supported routing conditions.
Vision input
GPT-5.4 Pro can process image inputs alongside text.
image_url content part alongside text messages.
OpenAI SDK
Call GPT-5.4 Pro through MixRoute's OpenAI-compatible endpoint.
base_url to https://api.mixroute.ai/v1; everything else follows the OpenAI style.
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Token cost estimator
Live estimate from this page's pricing, not an actual bill
This model has no cache-read price; caching is not counted
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FAQ
GPT-5.4 Pro is billed per use and the record publishes no free-tier allowance. The current published rates are input $30.00 per 1M tokens and output $180.00 per 1M tokens. Trial credit or promotional quota is tied to your account rather than to the model, so check the console before planning around a free tier.
One endpoint, a testable decision
Test this model and alternate routes with the same request format
Start from a real workload, then let quality, total cost, and failure conditions decide whether to send production traffic.