Cheaper overall
gpt-5.6-terra
44% lower blended rate
Higher benchmark scores
gpt-5.6-sol
leads on 12 of 14 figures
Cheaper cached input
gpt-5.6-terra
$0.20 vs $0.40, 50% less
Where each one wins
gpt-5.6-sol
- Higher overall intelligence (Intelligence Index) 47 vs 42.1
- Higher coding ability (Coding Index) 78.3 vs 76.7
- Higher multi-step tool use (Agentic Index) 50.2 vs 43.2
- Ahead on 9 more benchmark figures
gpt-5.6-terra
- Cheaper input tokens $2.00 vs $4.00, 50% less
- Cheaper output tokens $12.00 vs $20.00, 40% less
- Cheaper cached input $0.20 vs $0.40, 50% less
- Cheaper on all four workloads
- Higher support-agent performance (ฯยฒ-Bench Telecom) 86.3 vs 85.1
- Higher answer reliability (Omniscience Non-Hallucination) 12.1 vs 10.6
What four workloads cost
One run, and the same run a thousand times.
gpt-5.6-terra is cheaper on all four workloads, by much the same margin each time โ about 1.9 times, from $0.0080 against $0.0140 on a chat turn to $1.65 against $3.29 on a long document.
| Workload | gpt-5.6-sol | gpt-5.6-terra | ร1,000 | Difference |
|---|---|---|---|---|
| Chat turn 1,000 in / 500 out | $0.0140 | $0.0080 | $14.00 / $8.00 | gpt-5.6-terra is 43% cheaper |
| RAG answer 10,000 in / 800 out | $0.0560 | $0.0296 | $56.00 / $29.60 | gpt-5.6-terra is 47% cheaper |
| Agent loop 32,000 in / 700 out ร 20 calls | $0.6800 | $0.3680 | $680.00 / $368.00 | gpt-5.6-terra is 46% cheaper |
| Long document 400,000 in / 3,000 out | $3.29 | $1.65 | $3,290.00 / $1,654.00 | gpt-5.6-terra is 50% cheaper |
Price per 1M tokens
Above 272,000 input tokens the rates change, and the new rate applies to the whole request, not just the tokens past that point: gpt-5.6-sol's input goes from $4.00 to $8.00, and gpt-5.6-terra's input goes from $2.00 to $4.00. It does not change which of the two is cheaper.
| Context band | Price | gpt-5.6-sol | gpt-5.6-terra | Difference |
|---|---|---|---|---|
| Prompts up to 272,000 tokens | Input | $4.00 | $2.00 | gpt-5.6-terra is 50% cheaper |
| Prompts up to 272,000 tokens | Cached input | $0.40 | $0.20 | gpt-5.6-terra is 50% cheaper |
| Prompts up to 272,000 tokens | Output | $20.00 | $12.00 | gpt-5.6-terra is 40% cheaper |
| Prompts over 272,000 tokens | Input | $8.00 | $4.00 | gpt-5.6-terra is 50% cheaper |
| Prompts over 272,000 tokens | Cached input | $0.80 | $0.40 | gpt-5.6-terra is 50% cheaper |
| Prompts over 272,000 tokens | Output | $30.00 | $18.00 | gpt-5.6-terra is 40% cheaper |
Blended: gpt-5.6-sol $8.00, gpt-5.6-terra $4.50 per 1M โ one rate at 3:1 input to output, for comparing two models at a glance.
Both priced by OpenAI. Standard tier, pay-as-you-go.
Other pricing tiers
Both models offer Batch, Flex and Priority, worth up to 50% off their standard rates, and the cheaper model is the same one on every tier โ so the tier you buy changes the bill rather than the choice.
Every tier either model sells is here, so this is the whole price sheet. A saving is measured against that model's own standard rate โ how we read tiers.
| Tier | gpt-5.6-sol | gpt-5.6-terra | Cheaper |
|---|---|---|---|
| Batch | $2.00 in / $10.00 out 50% off Standard | $1.00 in / $6.00 out 50% off Standard | gpt-5.6-terra |
| Flex | $2.00 in / $10.00 out 50% off Standard | $1.00 in / $6.00 out 50% off Standard | gpt-5.6-terra |
| Priority | $8.00 in / $40.00 out | $4.00 in / $24.00 out | gpt-5.6-terra |
Benchmarks
They share 14 figures: gpt-5.6-sol leads on 12, gpt-5.6-terra on 2. The widest gap is 12.6 points, on factual accuracy (Omniscience Accuracy).
Overall intelligence
Intelligence Index โ Overall intelligence across reasoning, knowledge & math evals
gpt-5.6-sol ahead by 4.9
Coding ability
Coding Index โ Coding ability across software-engineering evals
gpt-5.6-sol ahead by 1.6
Multi-step tool use
Agentic Index โ Tool use & multi-step agent task performance
gpt-5.6-sol ahead by 7
Graduate-level science
GPQA Diamond โ Graduate-level questions in biology, chemistry & physics
gpt-5.6-sol ahead by 1.6
Expert-exam performance
Humanity's Last Exam โ Expert-level questions across many academic domains
gpt-5.6-sol ahead by 6.6
Instruction following
IFBench โ Precise following of detailed instructions
gpt-5.6-sol ahead by 1.5
Support-agent performance
ฯยฒ-Bench Telecom โ Tool-using agent tasks in a telecom support setting
gpt-5.6-terra ahead by 1.2
Long-context reasoning
AA-LCR โ Long-context reasoning across large inputs
gpt-5.6-sol ahead by 1
Scientific coding
SciCode โ Research-level scientific coding tasks
gpt-5.6-sol ahead by 2.8
Command-line work
Terminal-Bench Hard โ Complex command-line and terminal workflows
gpt-5.6-sol ahead by 3
Physics research reasoning
CritPt โ Unpublished physics research reasoning problems
gpt-5.6-sol ahead by 2.3
Real-world task performance
GDPval โ Economically valuable, real-world knowledge work
gpt-5.6-sol ahead by 7.8
Factual accuracy
Omniscience Accuracy โ Breadth of factual knowledge across domains
gpt-5.6-sol ahead by 12.6
Answer reliability
Omniscience Non-Hallucination โ How reliably the model avoids fabricated answers
gpt-5.6-terra ahead by 1.5
Each figure is that model's best published run, with the effort level named beside it โ where these scores come from.
Specifications
Both list the same capabilities, so nothing here separates them.
| Specification | gpt-5.6-sol | gpt-5.6-terra |
|---|---|---|
| Context window | 1,050,000 tokens | 1,050,000 tokens |
| Max output | 128,000 tokens | 128,000 tokens |
| Takes in | Text, image, file | Text, image, file |
| Puts out | Text | Text |
| Knowledge cutoff | 16 Feb 2026 | 16 Feb 2026 |
| Released | 9 Jul 2026 | 9 Jul 2026 |
| Status | Active | Active |
| Sold by | OpenAI, Perplexity | OpenAI, Perplexity |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Web search | Not listed | Not listed |
| Prompt caching | Yes | Yes |
| Code execution | Yes | Yes |
| Computer use | Not listed | Not listed |
| Open weights | Not listed | Not listed |
| Reasoning | Yes | Yes |
FAQs
- Is gpt-5.6-sol cheaper than gpt-5.6-terra?
- No โ the other way round. A 1,000-token prompt with a 500-token reply costs $0.0140 on gpt-5.6-sol and $0.0080 on gpt-5.6-terra, and the same model is cheaper on every workload on this page.
- How much do gpt-5.6-sol and gpt-5.6-terra cost per 1M tokens?
- gpt-5.6-sol costs $4.00 for input and $20.00 for output. gpt-5.6-terra costs $2.00 and $12.00. Standard pay-as-you-go rates, as of 23 Aug 2026.
- Which is better, gpt-5.6-sol or gpt-5.6-terra?
- On published benchmarks, gpt-5.6-sol. It leads on 12 of the 14 figures both models report, including overall intelligence (Intelligence Index), where it scores 47 against 42.1.
- Is Batch pricing cheaper for gpt-5.6-sol or gpt-5.6-terra?
- Batch input costs $2.00 on gpt-5.6-sol and $1.00 on gpt-5.6-terra, 50% below the standard rate on both.