Compare / head-to-head
DeepSeek V4 ProvsStep 3.5 Flash
DeepSeek V4 Pro leads 1 of 2 shared benchmarks. DeepSeek V4 Pro has the larger context window (1M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
1 – 0
DeepSeek V4 Pro leads · 1 tied
Cheaper per token
—
list price, input + output
Larger context
DeepSeek V4 Pro
1M tokens
Provider uptime (30d)
100% · —
DeepSeek · StepFun
DeepSeek V4 Pro
DeepSeek · released 2026-08-13
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Step 3.5 Flash
StepFun · released 2026-02-12
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- Context
- 256K
- Max out
- —
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 18 · 5 core
Quality
Benchmark matrix
2 shared · 9 only DeepSeek V4 Pro · 15 only Step 3.5 Flash| Benchmark | DeepSeek V4 Pro | Step 3.5 Flash | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 2 | ||||
| AIME 2026 | 96.7% ↗matharena ⚠ | 96.7% ↗matharena | 0 | Tie |
| LMArena Elo | 1450.6 ↗ | 1403.7 ↗ | +46.9 | DeepSeek V4 Pro |
| Only DeepSeek V4 Pro reports · 9 | ||||
| GPQA Diamond | 90.9% ↗epoch | not reported | — | — |
| DeepSWE v1.1 | 62.7% ↗ | not reported | — | — |
| FrontierMath Tier 4 v2 (Epoch AI run) | 2.4% ↗epoch | not reported | — | — |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 45.3% ↗epoch | not reported | — | — |
| Humanity's Last Exam (with tools) | 60% ↗ | not reported | — | — |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 96.7% ↗epoch | not reported | — | — |
| SimpleQA Verified | 47% ↗epoch | not reported | — | — |
| SWE-bench Verified (Epoch AI run) | 77.6% ↗epoch | not reported | — | — |
| Terminal-Bench 2.1 | 87.9% ↗ | not reported | — | — |
| Only Step 3.5 Flash reports · 15 | ||||
| SWE-bench Verified | not reported | 74.4% ↗ | — | — |
| AIME 2025 | not reported | 97.3% ↗ | — | — |
| BrowseComp | not reported | 51.6% ↗ | — | — |
| BrowseComp (with context manager) | not reported | 69% ↗ | — | — |
| BrowseComp-ZH | not reported | 66.9% ↗ | — | — |
| BrowseComp-ZH (with context manager) | not reported | 73.7% ↗ | — | — |
| GAIA (no file) | not reported | 84.5% ↗ | — | — |
| HMMT 2025 (Feb/Nov average) | not reported | 96.2% ↗ | — | — |
| IMOAnswerBench | not reported | 85.4% ↗ | — | — |
| LiveCodeBench v6 | not reported | 86.4% ↗ | — | — |
| ResearchRubrics | not reported | 65.3% ↗ | — | — |
| Tau2-Bench | not reported | 88.2% ↗ | — | — |
| Terminal-Bench 2.0 | not reported | 51% ↗ | — | — |
| xbench-DeepSearch 2025.05 | not reported | 83.7% ↗ | — | — |
| xbench-DeepSearch 2025.10 | not reported | 56.3% ↗ | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is DeepSeek V4 Pro minus Step 3.5 Flash in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | DeepSeek V4 Pro | Step 3.5 Flash | Edge |
|---|---|---|---|
| Context window | 1M tokens | 256K tokens | DeepSeek V4 Pro |
| Max output | 384K tokens | — | — |
| Input price / 1M | $0.435 ↗ | — | — |
| Output price / 1M | $0.87 ↗ | — | — |
| Cached input / 1M | $0.004 ↗ | — | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $1.31 | — | — |
| Modalities | text | text | Tie |
| Released | 2026-08-13 | 2026-02-12 | — |
| Cited benchmark scores | 11 | 18 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
DeepSeek V4 Pro vs …
Models sharing the most benchmarksMore matchups
Step 3.5 Flash vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
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