# gpt-5.5 — API, Pricing & Context Window 
Run OpenAI's gpt-5.5 on Vivgrid: a 1.05M-token flagship coding model for agents and CLIs, with geo-distributed acceleration and a unified API.

`gpt-5.5` is OpenAI's flagship model and Vivgrid's top recommendation for coding agents. It pairs a **1.05M-token context window** with strong multi-step reasoning, making it well suited for whole-repository refactors, long agent traces, and complex tool-calling workflows.

On Vivgrid, `gpt-5.5` is served through a single OpenAI-compatible endpoint with **geo-distributed acceleration across AMER and EMEA**, so requests are routed to the nearest compute region for lower latency. You can switch your agent to `gpt-5.5` from the Console without changing a line of application code.

## Specifications

|     |     |
| --- | --- |
| **Provider** | OpenAI |
| **Model ID** | `gpt-5.5` |
| **Best for** | Coding |
| **Context window** | 1,050,000 tokens |
| **Max output** | 128,000 tokens |
| **Modalities** | Text, Image |
| **Tool / function calling** | Yes |
| **Knowledge cutoff** | 2025-12 |
| **Acceleration** | ⚡ Geo-Distributed — AMER, EMEA |

## Pricing

Pricing in USD per 1M tokens, matching the provider's rates.

| Input | Cached input | Output |
| --- | --- | --- |
| $5.00 | $0.50 | $30.00 |

## Quick start

Call `gpt-5.5` through Vivgrid's unified, OpenAI-compatible endpoint. Get an API key from the [Vivgrid Console](https://console.vivgrid.com/).

```
curl https://api.vivgrid.com/v1/chat/completions \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.5",
    "messages": [\
      { "role": "user", "content": "Say hello in English, Chinese and Spanish." }\
    ],
    "stream": true
  }'
```

## Ideal use cases

- Autonomous coding agents and CLI tools (Codex, OpenCode, Claude Code-style flows)
- Large-context tasks: reading and editing entire codebases in one pass
- High-stakes reasoning where output quality outweighs token cost
- Multi-tool agents that chain function calls across long sessions

## Related models

- [gpt-5.4](/content/docs/models/gpt-5.4) — the prior flagship at a lower price point
- [gpt-5.3-codex](/content/docs/models/gpt-5.3-codex/index.html) — Codex-tuned variant on the Responses API
- [claude-opus-4-7](/content/docs/models/claude-opus-4-7/index.html) — Anthropic's frontier coding model

### On this page

[Ideal use cases](/content/docs/models/gpt-5.5#ideal-use-cases/index.html) [Related models](/content/docs/models/gpt-5.5#related-models/index.html)