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Model detail

gpt-5.5

Provided by OpenAI
Pay-as-you-go Dynamic pricing 2 tiers

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token context window (922K input, 128K output) with support for text and image inputs, enabling large-scale reasoning, coding, and multimodal workflows within a single system.

Model specs

Context length
1.05M
Max output
128K
I/O modalities
Text / Image
Released
2026-04

02

API endpoints

One MixRoute gateway, OpenAI-compatible

  • OpenAI-compatible /v1/chat/completions POST

03

Tiered pricing

Unit: /1M Tokens

Tier Input /1M Tokens Output /1M Tokens Cache read /1M Tokens
standard Length ≤ 272K $5.0000 $30.0000 $0.5000
long_context Length > 272K $10.0000 $45.0000 $1.0000

05

Selection summary

Quickly judge whether it fits your workload

What is this model good for?

Start with the documented use cases for gpt-5.5

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token context window (922K input, 128K output) with support for text and image inputs, enabling large-scale reasoning, coding, and multimodal workflows within a single system.

What should you check before using it?

Validate limits, pricing, and a representative workload

Review the current model limits and pricing record before production use.

How do you call it through MixRoute?

Use the documented endpoint and exact model ID

The model record lists OpenAI-compatible access via POST /v1/chat/completions with model ID gpt-5.5.

08

Token cost estimator

Live estimate from this page's pricing, not an actual bill

Share of the same prefix read repeatedly, up to 100%

09

FAQ

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token context window (922K input, 128K output) with support for text and image inputs, enabling large-scale reasoning, coding, and multimodal workflows within a single system.

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.