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GPT-5.5 Pro

Reviewed 2026-06-27
OpenAIopenai/gpt-5.5-pro
Context
1.05M
Price
$30/$180
Tooling
5/5
Deploy
Cloud API

Best for

  • Agentic workflows and tool calling
  • Writing and editing code
  • Complex reasoning and analysis
  • Long documents (~1.05M context)

Skip if

  • You need rock-bottom per-token cost
  • You need open weights to self-host

Capability scores

Tool calling5/5
Multi-step reasoning5/5

Specifications

Context window
1.05M tokens
VRAM
N/A (cloud-hosted)
License
proprietary
Pricing
$30/M input · $180/M output
Deployment
Cloud API

Our take

GPT-5.5 Pro from OpenAI offers a 1.05M-token context window and is well-suited to strong tool calling, multi-step reasoning, coding, long-context work. Pricing is $30/M input · $180/M output, billed per token through the provider API.

Watch for the trade-offs: output pricing is on the higher side; weights are closed, so you cannot self-host.

Compare to

Claude Fable 5
Anthropic
1M context · $10/M input · $50/M output
Claude Opus 4.8
Anthropic
1M context · $5/M input · $25/M output
Claude Sonnet 4.6
Anthropic
1M context · $3/M input · $15/M output
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