ColinBuilds · Current official OpenAI API pricing · promotional through at least 2026-11-21
GPT-5.6 Sol
- Input / 1M
- $4.00
- Output / 1M
- $20.00
- OpenAI-published context window
- 1,050,000 tokens
GPT-5.6 Sol / gpt-5.6-sol; OpenAI standard short-context row lists promotional $4.00 input, $0.40 cached input, $5.00 cache writes, and $20.00 output per 1M tokens. Long-context row is $8.00 / $0.80 / $10.00 / $30.00. OpenAI states Sol promotional pricing is available at least through 2026-11-21. Calculator uses the current promotional short-context input/output rates, not a guessed post-promo rate. · as of August 25, 2026
Compare models
Same per-1M input/output rates as above. Enter your monthly token volumes to compare bills.
GPT-5.6 Sol
- Input: 1M × $4.00 = $4.00
- Output: 1M × $20.00 = $20.00
- Total
- $24.00
GPT-4o
- Input: 1M × $2.50 = $2.50
- Output: 1M × $10.00 = $10.00
- Total
- $12.50
Difference
$11.50
GPT-5.6 Sol costs $11.50 more than GPT-4o.
Popular comparisons
37 total featuring GPT-5.6 Sol.
GPT-5.6 Sol is OpenAI’s flagship GPT-5.6 API model for complex professional work, long-context tasks, and tool-heavy workflows where capability matters more than choosing the cheapest tier.
What this model is
OpenAI’s model page describes GPT-5.6 Sol as the frontier model in the GPT-5.6 family. It is the Sol tier behind the bare gpt-5.6 alias, so requests sent to gpt-5.6 route to GPT-5.6 Sol.
The model supports text and image input with text output. OpenAI’s GPT-5.6 guidance says Sol is the flagship-capability option, while Terra targets a balance of intelligence and cost and Luna targets efficient high-volume work.
Pricing notes
The calculator on this page uses OpenAI’s official standard short-context pricing row for gpt-5.6-sol: $4.00 per 1M input tokens and $20.00 per 1M output tokens.
OpenAI labels this Sol row as promotional pricing available at least through November 21, 2026. The calculator stores that current promotional short-context rate. OpenAI’s live pricing table does not list a confirmed post-promo replacement rate, so this page does not invent one.
The same standard table lists cached input at $0.40 per 1M tokens and cache writes at $5.00 per 1M tokens for short context. The long-context row is $8.00 input, $0.80 cached input, $10.00 cache writes, and $30.00 output per 1M tokens. OpenAI’s model page says prompts with more than 272K input tokens are priced at 2x input and 1.5x output for the full request. Batch, Flex, and Fast mode have separate official rows. Those figures are noted here but are not used in the top-level calculator fields.
Benchmarks and specs
OpenAI’s model page lists GPT-5.6 Sol with a 1,050,000-token context window, a 128,000-token maximum output, and a Feb 16, 2026 knowledge cutoff. It also lists reasoning token support.
No benchmark score is shown until an exact benchmark source and model identity are matched to GPT-5.6 Sol.
Best fit
GPT-5.6 Sol is best for demanding API work: complex coding, deep analysis, long-document reasoning, agentic workflows, and applications where the strongest GPT-5.6 tier is worth the higher token price.
Use GPT-5.6 Terra or GPT-5.6 Luna when the workload is high-volume or cost-sensitive enough that the lower official OpenAI pricing matters more than choosing the flagship tier.