GPT-6 Luna vs GPT-6 Sol
Launched on the same day (September 22, 2026) as OpenAI's volume tier and work tier. Luna is 20x cheaper per token; Sol is the one OpenAI positions for complex work. GPT-6 Sol vs GPT-6 Luna in one table: list price, context window, output limit, cutoff and release date, with a cost calculator for your own monthly volume.
| Spec | GPT-6 Luna | GPT-6 Sol |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Released | 2026-09-22 | 2026-09-22 |
| Input / 1M tokens | $0.100 | $2.00 |
| Output / 1M tokens | $0.500 | $10.00 |
| Cached input / 1M | $0.010 | $0.200 |
| Batch input / output | $0.050 / $0.250 | $1.00 / $5.00 |
| Context window | 1.05M | 1.05M |
| Max output | 128K | 128K |
| Knowledge cutoff | 2026-05-18 | 2026-04-20 |
| Image input | yes | yes |
| API ID | gpt-6-luna | gpt-6-sol |
| Status | Generally available | Available |
Cost at your volume
list price, per monthPaste your usage instead of typing
Paste a line from a provider invoice, a usage dashboard, or an API response. We look for input and output token counts (JSON keys like input_tokens, prompt_tokens, completion_tokens, or text like "1.2M in, 300k out"). Nothing leaves your browser.
Examples that work: {"usage":{"input_tokens":1200000,"output_tokens":300000}} · 1.2M in, 300k out · GPT-6.1 Sol: 2.4B input tokens, 310M output tokens
Same token counts on both sides. Real bills differ: tokenizers differ, reasoning models bill thinking tokens as output, and caching or batch discounts apply differently. Rank all models →
Pick Luna if…
- Cost matters most: $0.60 vs $12.00 per 1M in + 1M out, 95% less.
- Your workload is cache-heavy: cached input is $0.010 vs $0.200 per 1M.
- You want the later knowledge cutoff (2026-05-18 vs 2026-04-20).
- Same provider: switching is a one-line model ID change (
gpt-6-luna). - Half the price of GPT-5.6 Luna ($0.20 / $1.20).
Pick GPT-6 Sol if…
- You have evals showing it beats Luna on your task by more than the 95% price gap.
- Same provider: switching is a one-line model ID change (
gpt-6-sol). - Half the price of GPT-5.6 Sol ($4 / $20).
Price difference, in words
Per million tokens, GPT-6 Luna lists at $0.100 in / $0.500 out, against $2.00 / $10.00 for GPT-6 Sol. That is 20× on input and 20× on output, or 95% less for a job that uses one million tokens each way ($0.60 vs $12.00).
With prompt caching, the gap moves: cached input is $0.010 on Luna and $0.200 on GPT-6 Sol. Agent loops that re-send a large system prompt every turn pay mostly cached-input rates.
- OpenAI model page: gpt-6-luna read 2026-10-08
context, max output, cutoff, pricing, features - OpenAI API pricing read 2026-10-08
standard, batch, flex, fast rates; GPT-5.6 Luna price - OpenAI API changelog (Sep 22, Sep 25, Oct 6, 2026 entries) read 2026-10-08
release date, image fix, Decisions API - OpenAI Developer Community: Announcing GPT-6 Sol and GPT-6 Luna read 2026-10-08
availability by product and tier
- OpenAI model page: gpt-6-sol read 2026-10-08
context, max output, cutoff, pricing - OpenAI API pricing read 2026-10-08
standard, batch, fast rates - OpenAI API changelog (Sep 22 and Sep 25, 2026 entries) read 2026-10-08
release date, image fix - Anthropic announcement: Claude Sonnet 5.5 (comparison table) read 2026-10-08
third-party vendor-published score