High-volume, cost-sensitive work
Either one
Both cost $11.25 per million tokens on a typical mix of three input tokens for every output token.
Chat Latest vs GPT-5.5: price, context and capabilities
Choose Chat Latest for the latest release and the most recent knowledge. Choose GPT-5.5 for very long inputs.
In short
- Both cost the same at the headline price ($11.25 / 1M tokens).
- GPT-5.5 reads more per request: 1.05M tokens against 400k.
- Chat Latest is the newer model (May 5, 2026, against Apr 24, 2026).
- Only GPT-5.5 offers reasoning.
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Very long inputs
Choose GPT-5.5
GPT-5.5 reads up to 1.05M tokens per request, against 400k for Chat Latest.
Latest release
Choose Chat Latest
Chat Latest is the newer release (May 5, 2026, against Apr 24, 2026 for GPT-5.5).
Most recent knowledge
Choose Chat Latest
Chat Latest was trained on data up to April 2026, against December 2025 for GPT-5.5.
Monthly cost at three volumes
| Volume | Chat Latest | GPT-5.5 | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $12.50 | $12.50 | = |
| Production: 20M input, 5M output tokens | $250.00 | $250.00 | = |
| Scale: 500M input, 100M output tokens | $5,500 | $5,500 | = |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| Chat Latest | GPT-5.5 | |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Category | Language models | Language models |
| Status | Generally available | Legacy |
| Headline price | $11.25 / 1M tokens | $11.25 / 1M tokens |
| Input | $5.00 / 1M tokens | $5.00 / 1M tokens |
| Output | $30.00 / 1M tokens | $30.00 / 1M tokens |
| Cached input | $0.50 / 1M tokens | $0.50 / 1M tokens |
| Context window | 400k | 1.05M |
| Max output | 128k | 128k |
| Released | May 5, 2026 | Apr 24, 2026 |
| Knowledge cutoff | April 2026 | December 2025 |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Tool calling, Structured output, Prompt caching, Batch API | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API |
| API model id | chat-latest | gpt-5.5 |
Benchmarks side by side
Leader in bold.
| Benchmark | Chat Latest | GPT-5.5 |
|---|---|---|
| Intelligence Index | No data | 38.4 |
| Terminal-Bench Hard | No data | 60.6% |
| SciCode | No data | 55.8% |
| GPQA Diamond | No data | 93.5% |
| Humanity's Last Exam | No data | 45.8% |
| IFBench (instruction following) | No data | 75.9% |
| τ²-Bench (agentic tool use) | No data | 93.9% |
| MMMU-Pro (visual reasoning) | No data | 79.9% |
| Long-context reasoning (AA-LCR) | No data | 84.3% |
Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.
Frequently asked questions
Should I choose Chat Latest or GPT-5.5?
Choose Chat Latest for the latest release and the most recent knowledge. Choose GPT-5.5 for very long inputs.
Which is cheaper, Chat Latest or GPT-5.5?
Both cost the same at the headline price ($11.25 / 1M tokens).
Which has the larger context window, Chat Latest or GPT-5.5?
GPT-5.5 reads more per request: 1.05M tokens against 400k.
What is the difference between Chat Latest and GPT-5.5?
Chat Latest is made by OpenAI and GPT-5.5 by OpenAI. Both cost the same at the headline price ($11.25 / 1M tokens). GPT-5.5 reads more per request: 1.05M tokens against 400k. Chat Latest is the newer model (May 5, 2026, against Apr 24, 2026). Only GPT-5.5 offers reasoning.
How much do Chat Latest and GPT-5.5 cost per month?
At 20 million input and 5 million output tokens a month, Chat Latest costs $250.00 and GPT-5.5 costs $250.00, at standard rates.
Which is newer, Chat Latest or GPT-5.5?
Chat Latest was released on May 5, 2026 and GPT-5.5 on Apr 24, 2026.