OpenAI
GPT-5.5 Instant
Compact GPT model for low-latency assistance and high-volume workloads
Model facts
- Context window
- 4K tokens
- Maximum output
- 128K tokens
- Cheapest paid input
- $5 per 1M tokens
- Cheapest paid output
- $30 per 1M tokens
- Open weights
- no
- Providers
- 2
Capabilities and modalities
reasoning, tool calling, structured output, attachments, temperature control, text, image, pdf.
Artificial Analysis benchmarks
Compare this model on the full LLM benchmark leaderboard.
| Configuration | AAI | Coding | Math | Output tokens/s |
|---|---|---|---|---|
| May 2026 | 34.3 | not measured | not measured | not measured |
| June 2026 | 29.2 | 39.4 | not measured | 148.0 |
Observed price history
- 2026-08-24: $5 input / $30 output per 1M tokens
API providers
- ZenMux — model id openai/gpt-5.5-instant; $5 input / $30 output per 1M tokens; provider documentation
- Arena — model id gpt-5.5-instant; not published input / not published output per 1M tokens; provider documentation