GPT-5.6 Terra vs GPT-6.1 Sol: Specs & Benchmark Comparison
GPT-5.6 Terra and GPT-6.1 Sol both come from OpenAI, GPT-5.6 Terra was released in July 2026, and GPT-6.1 Sol followed 2 months later in September 2026.
The two models share 7 published benchmarks. GPT-6.1 Sol leads on 7 of them. The widest gaps are on OSWorld 2.0, where GPT-6.1 Sol scores 71.4% against 50.2%; GDP.pdf, where GPT-6.1 Sol scores 32.0% against 24.7%. Averaged across everything we track, GPT-5.6 Terra sits at 59.0% and GPT-6.1 Sol at 58.5%.
On price the two are close: GPT-5.6 Terra costs $2 per million input tokens and $12 per million output tokens, GPT-6.1 Sol $2 and $10. Both accept a context window of about 1M tokens. Both accept text and images as input.
| Characteristic | GPT-5.6 Terra | GPT-6.1 Sol |
|---|---|---|
| Company | OpenAI | OpenAI |
| Release Date | July 9, 2026 | September 29, 2026 |
| Parameters | — | — |
| Multimodal | Yes | Yes |
| Context (input) | 1.1M | 1.1M |
| Context (output) | 128K | 128K |
| Input Price / 1M | $2.00 | $2.00 |
| Output Price / 1M | $12.00 | $10.00 |
| Average Score | 59.0% | 58.5% |
| Benchmarks | ||
| OSWorld 2.0 | 50.2% | 71.4% |
| GDP.pdf | 24.7% | 32.0% |
| HealthBench Professional | 57.7% | 64.2% |
| DeepSWE 1.1 | 70.0% | 75.2% |
| HealthBench Hard | 32.7% | 36.2% |
| HealthBench | 57.0% | 58.5% |
| HealthBench Consensus | 95.1% | 96.0% |
Visual Benchmark Comparison
Verdict
GPT-6.1 Sol leads in 2 out of 4 comparison categories.
Both models show comparable average scores: GPT-5.6 Terra — 0.6, GPT-6.1 Sol — 0.6.
GPT-6.1 Sol is 1.2x cheaper: input $2.00/1M vs $2.00/1M tokens.
Same context size: 1M tokens.
GPT-6.1 Sol is newer: released 9/29/2026 vs 7/9/2026.
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Frequently Asked Questions
Which is better for coding — GPT-5.6 Terra or GPT-6.1 Sol?
Which model is cheaper — GPT-5.6 Terra or GPT-6.1 Sol?
Which has a larger context window — GPT-5.6 Terra or GPT-6.1 Sol?
The GPT-5.6 Terra and GPT-6.1 Sol comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the GPT-5.6 Terra or GPT-6.1 Sol page. See also the complete list of AI model comparisons.