Head to head
DeepSeek V4 FlashvsStep 3.5 Flash
For tasks, about a month.
Verdict · measured basis
Step 3.5 Flash costs $0.0031 per solved task against
DeepSeek V4 Flash at $0.02 — ▼ 6.0x cheaper.
Over 200 tasks that is $3 a month.
On output token price alone Step 3.5 Flash looks 4.4x cheaper. The ranking holds, but the margin changes.
Verified pricing, pass rate and cost per solved task for DeepSeek V4 Flash and Step 3.5 Flash| Figure | DeepSeek V4 Flash | Step 3.5 Flash |
|---|
| Input $/Mtok | $0.44 | $0.1 |
|---|
| Output $/Mtok | $1.32 | $0.3 |
|---|
| Cached input $/Mtok | $0.014 | $0.1 |
|---|
| Pass rate | 73% | 50% |
|---|
| Cost per solved task | $0.02measured | $0.0031measured |
|---|
| Cost per month | $4 | $0.62 |
|---|
Cost per month against tasks per month · drag the marker
Solid measured · dashed modeled · dotted stale. The gap is the verdict.
Solvency Bench (solvency.dev) — first-party measurement · verified 2026-08-21 · prices from each provider's pricing page; measured rows ignore the tier · Methodology · All models at these settings