Model comparison
DeepSeek V4 Flash vs o3-mini
Head-to-head evidence from 2 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: DeepSeek V4 Flash #61 (Estimated); o3-mini #136 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. DeepSeek V4 Flash and o3-mini share 2 comparable benchmark results. 2 of 8 categories are comparable. 20 results are unique to DeepSeek V4 Flash; 8 to o3-mini.
Updated July 23, 2026- Shared results
- 2
- DeepSeek V4 Flash only
- 20
- o3-mini only
- 8
- Comparable categories
- 2 / 8
Pick DeepSeek V4 Flash if you want the stronger benchmark profile. o3-mini only becomes the better choice if knowledge is the priority or you want the stronger reasoning-first profile.
Confidence note. This is a partial-evidence comparison with 2 shared benchmark results across 2 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
DeepSeek V4 Flash is clearly ahead on the BenchAlign aggregate, 58.88 to 47.41. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
DeepSeek V4 Flash's sharpest advantage is in coding, where it averages 64.2 against 49.3. The single biggest benchmark swing on the page is SWE-bench Verified, 73.7% to 49.3%. o3-mini does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.
o3-mini is also the more expensive model on tokens at $1.10 input / $4.40 output per 1M tokens, versus $0.14 input / $0.28 output per 1M tokens for DeepSeek V4 Flash. That is roughly 15.7x on output cost alone. o3-mini is the reasoning model in the pair, while DeepSeek V4 Flash is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. DeepSeek V4 Flash gives you the larger context window at 1M, compared with 200K for o3-mini.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | DeepSeek V4 Flash | Δ | o3-mini |
|---|---|---|---|
| Knowledge | DeepSeek V4 Flash38.8 | Margin→ 38.4 | o3-mini77.2 |
| Coding | DeepSeek V4 Flash64.2 | Margin← 14.9 | o3-mini49.3 |
| Agentic | DeepSeek V4 Flash49.1 | MarginNo overlap | o3-miniNot measured |
| Math | DeepSeek V4 Flash40.8 | MarginNo overlap | o3-miniNot measured |
| Inst. Following | DeepSeek V4 FlashNot measured | MarginNo overlap | o3-mini93.9 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Verified
CodingA 73.7%B 49.3%Winner: DeepSeek V4 FlashΔ 24.4SWE-bench Verified: DeepSeek V4 Flash scored 73.7%; o3-mini scored 49.3%. DeepSeek V4 Flash wins this benchmark. - Source ↗
GPQA
KnowledgeA 71.2%B 77.2%Winner: o3-miniΔ 6GPQA: DeepSeek V4 Flash scored 71.2%; o3-mini scored 77.2%. o3-mini wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | DeepSeek V4 Flash | o3-mini | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | DeepSeek V4 Flash$0.14 input / $0.28 output | o3-mini$1.1 input / $4.4 output | DeepSeek V4 Flash has the lower combined listed price. |
| Generation speedtokens per second | DeepSeek V4 FlashNot available | o3-mini160 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | DeepSeek V4 FlashNot available | o3-mini7.12 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | DeepSeek V4 Flash1M | o3-mini200K | DeepSeek V4 Flash lists the larger context window. |
Benchmark Deep Dive
Agentic6 benchmarks
CodingDeepSeek V4 Flash wins5 benchmarks
Reasoning2 benchmarks
Knowledgeo3-mini wins10 benchmarks
| Benchmark | DeepSeek V4 Flash | o3-mini | Result |
|---|---|---|---|
| MMLU-ProSource | 83% | — | Not comparable |
| SimpleQASource | 23.1% | — | Not comparable |
| Chinese-SimpleQASource | 71.5% | — | Not comparable |
| GPQASource | 71.2% | 77.2% | o3-mini leads |
| GPQA-DSource | 71.2% | — | Not comparable |
| HLESource | 8.1% | — | Not comparable |
| MMLUSource | — | 86.9% | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 19.0% | Not comparable |
| AA-GPQA DiamondSource | — | 74.8% | Not comparable |
| AA-HLESource | — | 8.7% | Not comparable |
Math5 benchmarks
Multimodal1 benchmarks
| Benchmark | DeepSeek V4 Flash | o3-mini | Result |
|---|---|---|---|
| Design Arena WebsiteSource | 1238 | — | Not comparable |
Inst. Following1 benchmarks
| Benchmark | DeepSeek V4 Flash | o3-mini | Result |
|---|---|---|---|
| IFEvalSource | — | 93.9% | Not comparable |
Frequently Asked Questions (3)
Which is better, DeepSeek V4 Flash or o3-mini?
DeepSeek V4 Flash is ahead on BenchLM's BenchAlign leaderboard, 58.88 to 47.41. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 73.7% and 49.3%.
Which is better for knowledge tasks, DeepSeek V4 Flash or o3-mini?
o3-mini has the edge for knowledge tasks in this comparison, averaging 77.2 versus 38.8. Inside this category, GPQA is the benchmark that creates the most daylight between them.
Which is better for coding, DeepSeek V4 Flash or o3-mini?
DeepSeek V4 Flash has the edge for coding in this comparison, averaging 64.2 versus 49.3. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
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