DeepSeek V4.1 Flash vs GPT-6 Luna
Price and specs side by side · USD per 1M tokens · verified 2026-10-23
// side by side
| metric | DeepSeek V4.1 Flash | GPT-6 Luna |
|---|
| input / 1M | $0.20 | $0.10 |
| output / 1M | $0.60 | $0.50 |
| blended (3:1) | $0.30 | $0.20 |
| cache read / 1M | $0.006 | $0.01 |
| context | 1.05M | 1.05M |
| max output | 384K | 128K |
| input types | text · image | text · image · pdf |
| reasoning | yes | yes |
| tool calling | yes | yes |
| structured output | yes | yes |
| open weights | yes | no |
| released | 2026-09-10 | 2026-09-22 |
| knowledge cutoff | 2025-05 | 2026-05-18 |
| lab | DeepSeek | OpenAI |
// monthly cost scenarios
| workload | tokens in / out | DeepSeek V4.1 Flash | GPT-6 Luna |
|---|
| Chatbot | 10M / 2M | $3.20 | $2.00 |
| RAG app | 50M / 5M | $13.00 | $7.50 |
| Coding agent | 20M / 10M | $10.00 | $7.00 |
// verdict
- GPT-6 Luna is 33.3% cheaper than DeepSeek V4.1 Flash on a blended 3:1 input/output basis.
- GPT-6 Luna has the larger context window (1.05M vs 1.05M tokens).
- Chatbot (10M input / 2M output tokens per month): GPT-6 Luna costs $2.00 vs $3.20 for DeepSeek V4.1 Flash, saving $1.20 per month.
- RAG app (50M input / 5M output tokens per month): GPT-6 Luna costs $7.50 vs $13.00 for DeepSeek V4.1 Flash, saving $5.50 per month.
- Coding agent (20M input / 10M output tokens per month): GPT-6 Luna costs $7.00 vs $10.00 for DeepSeek V4.1 Flash, saving $3.00 per month.
// DeepSeek V4.1 Flash or GPT-6 Luna: which one to choose
- Choose GPT-6 Luna for cost-sensitive, high-volume workloads.
- Choose GPT-6 Luna for long documents and large codebases (1.05M-token context).
- Choose DeepSeek V4.1 Flash if you want open weights you can self-host.