Long context

gpt-5.5 API pricing

OpenAI's GPT series — broad general capability, wide ecosystem, and the native models behind Codex CLI.

Model IDopenai/gpt-5.5

ChatStreamingTool callingVision

Get API Key Run your first request

Call summary

Input

$5.00$0.50/ 1M tokens

Cache write $0.50

Output

$22.50$2.25/ 1M tokens

Cache read $0.125

Context Window

1.05M

API Endpoints

Available Configurations

gpt-5.5 API endpoints

One API key — call this model through any of the 2 endpoints below.

POST/v1/chat/completionsOpenAI-compatible · Works for every model

Docs

POST/v1/responsesResponses API · Native for Codex CLI

Docs

Production reliability

Privacy-safe aggregates from real Router One model calls, so you can assess stability and response latency before integrating.

Successful response share

98.89%

Success 2xx

98.89%

Rate limit 429

0.07%

Server 5xx

1.03%

TPS

56.76

tokens/s

Avg. time to first token

10.85 s

Avg. latency

25.3 s

Includes production requests ending in 2xx, 429, or 5xx. Average latency uses successful requests; time to first token and TPS require complete observations from successful streams. Public thresholds are 100 requests and 5 independent principals.

Updated Sep 9, 2026, 8:59 PM UTC

More GPT models on Router One

6 other GPT models on the same gateway and API key — each page lists endpoints, posted price, and context window.

codex-auto-review$0.50 in / $3.00 out per 1M1.05M context gpt-5.3-codex-spark$0.4314 in / $3.4521 out per 1M400K context gpt-5.6-sol$0.50 in / $4.00 out per 1M1.05M context gpt-5.6-terra$0.25 in / $1.50 out per 1M1.05M context gpt-6-astra$2.00 in / $10.00 out per 1M1.05M context gpt-image-2$0.50 per image

gpt-5.5 compared with other models

Spec and price matchups against peer models.

GPT-5.5vsClaude Sonnet 5 Claude Opus 4.8vsGPT-5.5 GPT-5.6 SolvsGPT-5.5 Grok 4.5vsGPT-5.5

Call gpt-5.5 from your code

The same API key works across all 2 endpoints below.

Endpoint

/v1/chat/completions

Model ID

openai/gpt-5.5

Routing mode

auto

Request example

bash

curl -X POST \
  https://api.router.one/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "openai/gpt-5.5",
    "messages": [
      {"role": "user", "content": "Hello!"}
    ]
  }'

Get API Key

gpt-5.5 at a glance

gpt-5.5 is a GPT-series text model on Router One. Posted rate: $0.50 in / $2.25 out per 1M tokens (was $5.00 in / $22.50 out). Context window: 1.05M tokens. Endpoints: POST /v1/chat/completions (OpenAI-compatible), POST /v1/responses (Responses API, the Codex CLI path).

gpt-5.5 FAQ

How much does gpt-5.5 cost on Router One?

gpt-5.5 is billed per token on Router One: $0.50 in / $2.25 out per 1M tokens, pay as you go.

Which endpoints serve gpt-5.5?

gpt-5.5 is served on 2 endpoints — POST /v1/chat/completions (OpenAI-compatible), POST /v1/responses (Responses API, the Codex CLI path). The same Router One API key works on each.

What is gpt-5.5's context window?

gpt-5.5 accepts up to 1.05M tokens of context per request on Router One.

Start using gpt-5.5

Create an API key and call gpt-5.5 at $0.50 in / $2.25 out per 1M tokens on Router One — pay as you go, with per-request cost and latency visibility.

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