GPT-5.6 Sol vs GPT-5.6 Terra
OpenAI vs OpenAI · Prices checked 12 August 2026
GPT-5.6 Terra is the cheaper of the two by a wide margin: $5.00 per million tokens blended against $12.50, roughly 2.5× less. A single 100K-input, 10K-output job costs $0.320 on GPT-5.6 Terra against $0.800 on GPT-5.6 Sol.
GPT-5.6 Sol leads on 2 of the 2 benchmarks both models report. The widest gap is on LMArena Elo, where GPT-5.6 Sol leads by 16 points. Both offer the same 1,050,000-token context window. GPT-5.6 Sol was released Jul 2026; GPT-5.6 Terra Jul 2026.
Pricing and capacity
| Metric | GPT-5.6 Sol | GPT-5.6 Terra | Difference |
|---|---|---|---|
| Input / 1M tokens | $5.00 | $2.00 | 2.5× |
| Output / 1M tokens | $30.00 | $12.00 | 2.5× |
| Blended · 70/30calculated | $12.50 | $5.00 | 2.5× |
| Blended · 50/50calculated | $17.50 | $7.00 | 2.5× |
| Blended · 80/20calculated | $10.00 | $4.00 | 2.5× |
| Blended · 20/80calculated | $25.00 | $10.00 | 2.5× |
| Job cost · 100K + 10Kcalculated | $0.800 | $0.320 | 2.5× |
| Job cost · 1M + 100Kcalculated | $8.00 | $3.20 | 2.5× |
| Context window | 1,050,000 | 1,050,000 | level |
Input and output rates are as published by each provider. Blended and job-cost rows are calculated comparison metrics, not published prices — how they are derived.
Benchmarks
| Benchmark | GPT-5.6 Sol | GPT-5.6 Terra | Leader |
|---|---|---|---|
| GPQA Diamond | 94.6% | 92.9% | GPT-5.6 Sol |
| LMArena Elo | 1481 Elo | 1465 Elo | GPT-5.6 Sol |
Only suites both models report are listed, so a missing score is never shown as a loss. Figures are provider-published or from public leaderboards and are not independently re-run.
What each model is for
GPT-5.6 Sol
OpenAI · Frontier
The flagship tier of the GPT-5.6 family, aimed at complex reasoning, long-horizon agentic work, coding, biology and cybersecurity. In OpenAI's naming the number is the generation and Sol is a durable capability tier, so Sol advances on its own cadence rather than being replaced by the next decimal. Standard short-context pricing is $5/$30 per MTok with cached input at $0.50; requests above 272K tokens are billed at the long-context rate of $10/$45.
- Frontier reasoning
- Long-horizon agentic execution
- Coding and code review
- Programmatic tool calling in the Responses API
GPT-5.6 Terra
OpenAI · Balanced
The balanced everyday tier of GPT-5.6, which OpenAI describes as competitive with GPT-5.5 at a lower price. Terra is the cheaper path for scoped implementation work and first-pass review, where Sol's full reasoning budget is more than the task needs. Standard short-context pricing is $2/$12 per MTok with cached input at $0.20, roughly 60% below Sol for the same context window.
- GPT-5.5-class performance at lower cost
- Scoped implementation work
- First-pass code review
- Tool calling
Frequently asked questions
Which is cheaper, GPT-5.6 Sol or GPT-5.6 Terra?
GPT-5.6 Terra is the cheaper of the two by a wide margin: $5.00 per million tokens blended against $12.50, roughly 2.5× less. A single 100K-input, 10K-output job costs $0.320 on GPT-5.6 Terra against $0.800 on GPT-5.6 Sol. Blended cost weights input at 70% and output at 30%; price your own token split for an exact answer, since the cheaper model on a blended basis is not always cheaper for your workload.
Which performs better, GPT-5.6 Sol or GPT-5.6 Terra?
GPT-5.6 Sol leads on 2 of the 2 benchmarks both models report. The widest gap is on LMArena Elo, where GPT-5.6 Sol leads by 16 points. These are the figures each provider or public leaderboard publishes, not results we re-run, and a benchmark average can hide the specific behaviour your workload depends on.
Which has the larger context window, GPT-5.6 Sol or GPT-5.6 Terra?
Both offer the same 1,050,000-token context window. The context window caps everything in a single request: prompt, retrieved documents, conversation history and the model’s own output all share it.
Can I compare GPT-5.6 Sol and GPT-5.6 Terra on my own numbers?
Yes. Open both in the side-by-side comparison tool to see every field at once, or use the token calculator to price your actual prompt and monthly request volume against each model. Both are free and need no sign-up.
Price it for your own workload
Related matchups
Terms used on this page
Prices and scores are recomputed on every deploy from the catalogue. Prices checked 12 August 2026.