ColinBuilds · Current official OpenAI API pricing
GPT-5.6 Luna
- Input / 1M
- $0.20
- Output / 1M
- $1.20
- OpenAI-published context window
- 1,050,000 tokens
GPT-5.6 Luna / gpt-5.6-luna; OpenAI standard short-context row lists $0.20 input, $0.02 cached input, $0.25 cache writes, and $1.20 output per 1M tokens. Long-context row is $0.40 / $0.04 / $0.50 / $1.80. Unlike Sol, the live pricing table does not label Luna as promotional. · 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 Luna
- Input: 1M × $0.20 = $0.20
- Output: 1M × $1.20 = $1.20
- Total
- $1.40
GPT-4o
- Input: 1M × $2.50 = $2.50
- Output: 1M × $10.00 = $10.00
- Total
- $12.50
Difference
$11.10
GPT-4o costs $11.10 more than GPT-5.6 Luna.
Popular comparisons
37 total featuring GPT-5.6 Luna.
GPT-5.6 Luna is OpenAI’s cost-sensitive GPT-5.6 API model for high-volume applications that still need the GPT-5.6 family rather than an older or unrelated model line.
What this model is
OpenAI’s model page describes GPT-5.6 Luna as a GPT-5.6 model designed for cost-sensitive, high-volume workloads. It roughly corresponds to the nano model tier used in earlier GPT-5 families.
The model supports text and image input with text output. OpenAI’s GPT-5.6 guidance positions Luna as the efficient high-volume option below Terra and Sol.
Pricing notes
The calculator on this page uses OpenAI’s official standard short-context pricing row for gpt-5.6-luna: $0.20 per 1M input tokens and $1.20 per 1M output tokens.
OpenAI’s pricing page also lists cached input at $0.02 per 1M tokens and cache writes at $0.25 per 1M tokens for the standard short-context row. The long-context row is $0.40 input, $0.04 cached input, $0.50 cache writes, and $1.80 output per 1M tokens. The 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.
Unlike GPT-5.6 Sol, the live OpenAI pricing table does not attach a promotional end date to Luna. This page treats the listed short-context $0.20/$1.20 row as the current standard rate.
Benchmarks and specs
OpenAI’s model page lists GPT-5.6 Luna 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 Luna.
Best fit
GPT-5.6 Luna is best for high-volume assistants, extraction, classification, routing, lightweight coding support, and repeated agent steps where official OpenAI pricing needs to stay low.
Use Terra or Sol when the task needs a stronger GPT-5.6 tier, especially for complex reasoning, difficult coding, or quality-first analysis.