GPT-5.5 vs GPT-5.6 Sol
Pricing, benchmarks, and use case comparison
Quick take
- •Both are from OpenAI; compare the specs below to match one to your latency and budget needs.
Specs comparison
| GPT-5.5 | GPT-5.6 Sol | |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Type | Closed source | Closed source |
| Context window | ✓1,050,000 tokens (128,000 max output) | Not announced |
| Input / 1M tokens | $5.00 | $5.00 |
| Output / 1M tokens | $30.00 | $30.00 |
| Release date | 2026-04 | 2026-06 |
Benchmarks
| Benchmark | GPT-5.5 | GPT-5.6 Sol |
|---|---|---|
| SWE-bench Verified | 82.6% | - |
| SWE-bench Pro | 58.6% | - |
| Terminal-Bench 2.1 | - | 88.8% |
| Terminal-Bench 2.1 (Ultra) | - | 91.9% |
| ExploitBench | - | competitive with Mythos Preview |
Scores sourced from official provider release posts and independent benchmark aggregators.
Which should you choose?
Choose GPT-5.5 if...
- →Complex professional coding, data analysis, and multi-tool agentic workflows
- →Long-document or large-codebase tasks needing a 1M+ context window
- →You want OpenAI's recommended default frontier model for new projects
Choose GPT-5.6 Sol if...
- →You are an approved preview partner needing the most capable model for agentic software engineering
- →Complex multi-step tasks that benefit from subagent orchestration (Ultra) or maximum reasoning depth (max)
- →Frontier scientific research, professional knowledge work, or security-sensitive workloads