GPT-5.6 Sol vs GPT-5.6 Terra
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
| Specification |
GPT-5.6 SolIntro price
by OpenAI
|
by OpenAI
|
|---|---|---|
| Overview | ||
| Status | Current flagship | Current flagship |
| Released | Jul 9, 2026 | Jul 9, 2026 |
| Pricing per million tokens | ||
| Input | $4.00/Mtok | $2.00/Mtok |
| Output | $20.00/Mtok | $12.00/Mtok |
| Blended avg | $8.00/Mtok | $4.50/Mtok |
| Cached input | $0.400/Mtok | $0.200/Mtok |
| Price basis | OpenAI labels this promotional pricing and states it is "available at least through November 21, 2026". That is a floor, not a reversion date — OpenAI publishes no date on which the rate goes back up, so no reversion is claimed here and no countdown is implied. Until 2026-08-21 this model billed $5 input / $0.50 cached input / $30 output per 1M tokens. OpenAI's rate card also prices this model by context length: the tracked figure is the short-context tier, and prompts over the short-context threshold bill at the long-context tier of $8 input / $0.80 cached input / $10 cache write / $30 output per 1M tokens. Cache writes bill at 1.25x the uncached input rate. | — |
| Specifications | ||
| Context window | 1M tokens | 1M tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimage
|
textimage
|
| Benchmarks source: Vellum LLM Leaderboard | ||
| Avg benchmark score | 83.8 | 87.7 |
| Perf / dollar | 10.5 | 19.5 |
| GPQA Diamond | 94.6 | 92.9 |
| Terminal-Bench 2.1 | 88.8 | 82.5 |
| SWE-Bench Verified | 96.2 | — |
| BrowseComp | 92.2 | — |
| OSWorld-Verified | 62.6 | — |
| Humanity's Last Exam | 47.2 | — |
| ARC-AGI 2 | 92.5 | — |
| HumanEval | 96.2 | — |
| AutoBench | 18.1 | — |
| Independent composite scores each on its own scale — not part of the average above | ||
| AA Intelligence Index | 60.9 | 56.6 |
| AA Agentic Index | 57.8 | 50.2 |
| AA-Omniscience Index (−100–100) | 22 | 0.1 |
| GDPval-AA v2 | 1711.4 ELO | 1565.5 ELO |
| LMSYS Chatbot Arena | 1482.2 ELO | — |
| Providers | ||
| Available from |
OpenAI — $4.00/$20.00/Mtok
|
OpenAI — $2.00/$12.00/Mtok
|
Cost at scale
1M tokens · 50/50 input/output| Volume | GPT-5.6 Sol | GPT-5.6 Terra | Savings |
|---|---|---|---|
| 1M tokens | $8 | $4.5 | $3.5 (43.8%) |
| 10M tokens | $80 | $45 | $35 (43.8%) |
| 100M tokens | $800 | $450 | $350 (43.8%) |
| 1000M tokens | $8000 | $4500 | $3500 (43.8%) |
When to pick which
distilled from the pricing and spec data above- this pairing gives GPT-5.6 Sol no edge on price, context, cache discount, or measured performance — pick it only for qualitative fit (ecosystem, compliance, model behavior on your prompts)
- cost dominates: $4.50/Mtok blended vs $8.00 — 43.8% less on the same 50/50 token mix
- raw capability matters more than price: 87.7 vs 83.8 average benchmark score
Price movement
recorded changes since we began tracking each model · last checked Aug 28, 2026| Model | Changes | Latest move | Old → new $/M |
|---|---|---|---|
| GPT-5.6 Sol | 1 | price cut on Aug 21, 2026 | $5/$30 → $4/$20/Mtok |
| GPT-5.6 Terra | 1 | price cut on Aug 1, 2026 | $2.5/$15 → $2/$12/Mtok |
The cheaper option here — GPT-5.6 Terra costs $4.50/Mtok blended on OpenAI.
Summary
GPT-5.6 Sol by OpenAI costs $4.00/Mtok input and $20.00/Mtok output, with a 1M-token context window. It supports text, image input.
GPT-5.6 Terra by OpenAI costs $2.00/Mtok input and $12.00/Mtok output, with a 1M-token context window. It supports text, image input.
On a blended cost basis, GPT-5.6 Terra is 43.8% cheaper than GPT-5.6 Sol.
On benchmarks, GPT-5.6 Terra scores higher (87.7 vs 83.8) on average. In terms of value, GPT-5.6 Terra has better performance per dollar (19.5 vs 10.5).
Note: Pricing is per million tokens. Actual costs vary with usage patterns, prompt caching, and batch discounts. Always verify against official provider pricing pages.