DeepSeek V4.1 Flash vs GPT-5.6 Sol.
Verdict by category, tale of the tape, shared benchmarks only, and cost at three workloads — all from the tracked data.
Verdict by category
| Category | DeepSeek V4.1 Flash | GPT-5.6 Sol | Winner |
|---|---|---|---|
| League Score | 75.4 | 82.2 | GPT-5.6 Sol |
| Coding (SWE-bench %) | — | — | — |
| Reasoning (GPQA %) | 90.9 | 94.6 | GPT-5.6 Sol |
| Context (tokens) | 1000000 | 1050000 | GPT-5.6 Sol |
| Speed (tok/s) | 213 | — | — |
| Price (blended $/1M) | $0.52 | $8.00 | DeepSeek V4.1 Flash (cheaper) |
Tale of the tape
| Spec | DeepSeek V4.1 Flash | GPT-5.6 Sol |
|---|---|---|
| Maker | DeepSeek | OpenAI |
| Released | Sep 10, 2026 | Jul 9, 2026 |
| League Score | 75 | 82 |
| Context | 1,000,000 tokens | 1,050,000 tokens |
| Max output | 384,000 | 128,000 |
| $/1M input | $0.30 | $4.00 |
| $/1M output | $1.20 | $20.00 |
| Weights | Open | Closed |
| Speed | 213 t/s | — |
Head-to-head benchmarks (shared only)
| Benchmark | DeepSeek V4.1 Flash | GPT-5.6 Sol |
|---|---|---|
| LiveBench overall | 77.3 | 76.3 |
| GPQA Diamond | 90.9 | 94.6 |
Cost at three workloads
| Workload | DeepSeek V4.1 Flash | GPT-5.6 Sol |
|---|---|---|
| Light — 1M in / 250K out | $0.60 | $9.00 |
| Standard — 10M in / 2.5M out | $6.00 | $90.00 |
| Long-context — 50M in / 5M out | $21.00 | $300.00 |
The pick
Pick DeepSeek V4.1 Flash if you want the lower running cost; you want downloadable weights / self-hosting.
Pick GPT-5.6 Sol if you want the higher overall League Score; you need the bigger context window.
All figures from the model database — sources and dates on each model page. Cost your own workload or compare a different pair.
Frequently asked questions
Which is better overall, DeepSeek V4.1 Flash or GPT-5.6 Sol?
GPT-5.6 Sol leads on overall League Score, 82 to 75 — a gap of 7 points on a composite of sourced benchmarks. That is overall form, not every category: check the per-category verdicts before choosing.
Which is cheaper, DeepSeek V4.1 Flash or GPT-5.6 Sol?
DeepSeek V4.1 Flash is cheaper: $0.52 vs $8.00 blended per 1M tokens (3:1 input/output mix) — about 15.2x less per token.
Which has the bigger context window, DeepSeek V4.1 Flash or GPT-5.6 Sol?
GPT-5.6 Sol, with 1.1M of context against 1M for DeepSeek V4.1 Flash.
Which is better at reasoning, DeepSeek V4.1 Flash or GPT-5.6 Sol?
GPT-5.6 Sol leads on GPQA Diamond, 94.6% vs 90.9% on graduate-level science questions.
Are DeepSeek V4.1 Flash and GPT-5.6 Sol open source?
DeepSeek V4.1 Flash is open weights — it can be downloaded and self-hosted; GPT-5.6 Sol is closed weights — API access only.