GPT-5.6 Sol API pricing
Official OpenAI list price, last checked Oct 29, 2026. Updated Oct 29, 2026.
GPT-5.6 Sol costs $4 per 1M input tokens and $20 per 1M output tokens, cached input at $0.40, per OpenAI's official pricing page (checked Oct 29, 2026). It's a premium-priced model: number 70 of 77 by blended price ($8 per 1M tokens at a 3 to 1 input to output mix). On LMArena's Text Arena it ranks #10 of 51 models we price (relative score 33 out of 100). Cheaper pick: Gemini 3.8 Flash scores 54 against 33 on the same board at $1.50 blended, 5.3x less. It's also one of our value picks for long documents.
GPT-5.6 Sol price per million tokens
| GPT-5.6 Sol price per million tokens | USD |
|---|---|
| Input | $4 |
| Cached input | $0.40 |
| Output | $20 |
| Blended, 3 parts input to 1 part output | $8 |
| Context window | Not listed |
Official note from OpenAI: Promotional price, at least through Nov 21, 2026.
What GPT-5.6 Sol costs for real work
List-price estimates for a month, no discounts. Our math, not a quote: change the token counts in the plan vs API calculator.
| Workload | Tokens a month | GPT-5.6 Sol | Claude Opus 5.5 | Gemini 4 Argon |
|---|---|---|---|---|
| Light: a side project or personal assistant | 2M in, 0.5M out | $18.00 | $18.00 | $9.00 |
| Medium: a small team or one product feature | 20M in, 5M out | $180 | $180 | $90.00 |
| Heavy: a production app | 200M in, 50M out | $1,800 | $1,800 | $900 |
| Medium with 80% of input cached | 20M in (16M cached), 5M out | $122 | $119 | $59.60 |
How GPT-5.6 Sol ranks on LMArena
Relative score: 100 is the top model we price on that board. Rank is among the models in our price table, not the full leaderboard.
| Board | Rank | Score /100 |
|---|---|---|
| Chat (Text Arena) | #10 of 51 | 33 |
| Creative writing (Text Arena creative writing) | #8 of 51 | 33 |
| Roleplay and characters (Text Arena multi-turn) | #9 of 51 | 22 |
| Reasoning and math (Text Arena math) | #15 of 51 | 35 |
| Vision (Vision Arena) | #8 of 33 | 69 |
| Long documents (Document Arena) | #3 of 11 | 96 |
| Cheap bulk and agents (Agent Arena) | #9 of 34 | 57 |
Closest rivals to GPT-5.6 Sol
The models nearest in price, other makers first. Ranks are on Text Arena, where we have them.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| Claude Opus 5.5 | $4 / $20 | $8 | Claude Opus 5.5 wins: same price, higher score. Compare |
| Muse Wonder 1.0 | $4 / $20 | $8 | Muse Wonder 1.0 wins: same price, higher score. Compare |
| Kimi K3.1 Pro Highspeed | $4 / $20 | $8 | Same price, no score to separate them. Compare |
| Kimi K3 | $3 / $15 | $6 | Kimi K3 wins on both. Compare |
Cheaper alternatives to GPT-5.6 Sol
At least 40% cheaper blended, best LMArena score first.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| Gemini 4 Argon | $2 / $10 | $4 | Gemini 4 Argon wins on both. Compare |
| Gemini 3.8 Flash | $0.75 / $3.75 | $1.50 | Gemini 3.8 Flash wins on both. Compare |
| Muse Spark 1.3 | $1.25 / $4.25 | $2 | Muse Spark 1.3 wins on both. Compare |
More from OpenAI
- GPT-5.5$5 in, $30 out per 1M
- GPT-5.6 Terra$2 in, $12 out per 1M
- GPT-6.1 Sol$2 in, $10 out per 1M
- GPT-6 Sol$2 in, $10 out per 1M
- GPT-6.1 Terra$1 in, $5 out per 1M
FAQ
How much does the GPT-5.6 Sol API cost per million tokens?
$4 per 1M input tokens and $20 per 1M output tokens, plus $0.40 per 1M for cached input, as of Oct 29, 2026. A typical 3 to 1 input to output mix works out to $8 per 1M tokens.
Does GPT-5.6 Sol charge more for long prompts?
OpenAI doesn't list a long-prompt surcharge for GPT-5.6 Sol. Its pricing note says: Promotional price, at least through Nov 21, 2026.
Is GPT-5.6 Sol cheaper than Claude Opus 5.5?
About the same. A medium month (20M input and 5M output tokens) costs $180 on GPT-5.6 Sol and $180 on Claude Opus 5.5 at list price. On Text Arena, GPT-5.6 Sol ranks #10 and Claude Opus 5.5 #2.
How does GPT-5.6 Sol rank on LMArena?
On Text Arena it is #10 of 51 models we price, with a relative score of 33 out of 100. It ranks on 7 of 8 boards we track.
What is a cheaper alternative to GPT-5.6 Sol?
Gemini 4 Argon costs $2 in and $10 out per 1M tokens, about 2.0x less blended, and scores 100 on Text Arena against 33 for GPT-5.6 Sol.
Where does this GPT-5.6 Sol price come from?
From OpenAI's official pricing page, which we check every day. This page was last checked Oct 29, 2026.