Model comparison
Claude 4 Sonnet vs Step 3.7 Flash
Head-to-head evidence from 15 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
BenchAlign evidence: Claude 4 Sonnet supported; Step 3.7 Flash estimated. Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude 4 Sonnet and Step 3.7 Flash share 15 comparable benchmark results. 1 of 8 categories are comparable. 2 results are unique to Claude 4 Sonnet; 15 to Step 3.7 Flash.
Updated July 16, 2026- Shared results
- 15
- Claude 4 Sonnet only
- 2
- Step 3.7 Flash only
- 15
- Comparable categories
- 1 / 8
Pick Step 3.7 Flash if you want the stronger benchmark profile. Claude 4 Sonnet only becomes the better choice if coding is the priority or you would rather avoid the extra latency and token burn of a reasoning model.
Confidence note. This is a partial-evidence comparison with 15 shared benchmark results across 6 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Step 3.7 Flash is clearly ahead on the provisional aggregate, 57 to 48. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude 4 Sonnet is also the more expensive model on tokens at $3.00 input / $15.00 output per 1M tokens, versus $0.20 input / $1.15 output per 1M tokens for Step 3.7 Flash. That is roughly 13.0x on output cost alone. Step 3.7 Flash is the reasoning model in the pair, while Claude 4 Sonnet 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. Step 3.7 Flash gives you the larger context window at 256K, compared with 200K for Claude 4 Sonnet.
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 | Claude 4 Sonnet | Δ | Step 3.7 Flash |
|---|---|---|---|
| Coding | Claude 4 Sonnet72.7 | Margin← 16.4 | Step 3.7 Flash56.3 |
| Agentic | Claude 4 SonnetNot measured | MarginNo overlap | Step 3.7 Flash66.4 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude 4 Sonnet | Step 3.7 Flash | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude 4 Sonnet$3 input / $15 output | Step 3.7 Flash$0.2 input / $1.15 output | Step 3.7 Flash has the lower combined listed price. |
| Generation speedtokens per second | Claude 4 Sonnet40 tok/s | Step 3.7 FlashNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude 4 Sonnet1.33 s | Step 3.7 FlashNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude 4 Sonnet200K | Step 3.7 Flash256K | Step 3.7 Flash lists the larger context window. |
Benchmark Deep Dive
Agentic13 benchmarks
| Benchmark | Claude 4 Sonnet | Step 3.7 Flash | Result |
|---|---|---|---|
| τ²-bench resultsSource | 52.3% | 98.5% | Step 3.7 Flash leads |
| Gert LabsSource | 39.66% | 51.57% | Step 3.7 Flash leads |
| JobBenchSource | 18.4% | — | Not comparable |
| Terminal-Bench 2.0Source | — | 59.5% | Not comparable |
| BrowseCompSource | — | 75.8% | Not comparable |
| DeepSearchQASource | — | 92.8% | Not comparable |
| GDPval-AASource | — | 25.9% | Not comparable |
| ToolathlonSource | — | 49.5% | Not comparable |
| Claw-EvalSource | — | 67.1% | Not comparable |
| HLE w/ toolsSource | — | 47.2% | Not comparable |
| AA Agentic IndexSource | — | 21.5% | Not comparable |
| GDPval-AASource | — | 1017 | Not comparable |
| APEX-Agents-AASource | — | 14.8% | Not comparable |
CodingClaude 4 Sonnet wins6 benchmarks
| Benchmark | Claude 4 Sonnet | Step 3.7 Flash | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 72.7% | — | Not comparable |
| Terminal-Bench HardSource | 27.3% | 35.6% | Step 3.7 Flash leads |
| AA-SciCodeSource | 37.3% | 40.0% | Step 3.7 Flash leads |
| SWE-bench ProSource | — | 56.3% | Not comparable |
| Terminal-Bench 2.0Source | — | 59.5% | Not comparable |
| AA Coding IndexSource | — | 39.6% | Not comparable |
Reasoning2 benchmarks
Knowledge6 benchmarks
| Benchmark | Claude 4 Sonnet | Step 3.7 Flash | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 25.5% | 30.3% | Step 3.7 Flash leads |
| AA-GPQA DiamondSource | 68.3% | 80.9% | Step 3.7 Flash leads |
| AA-HLESource | 4.0% | 19.9% | Step 3.7 Flash leads |
| AA-Omniscience IndexSource | -9.2% | -37.5% | Claude 4 Sonnet leads |
| AA-Omniscience AccuracySource | 22.4% | 25.4% | Step 3.7 Flash leads |
| AA-Omniscience Hallucination RateSource | 40.8% | 84.4% | Claude 4 Sonnet leads |
Multimodal4 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude 4 Sonnet | Step 3.7 Flash | Result |
|---|---|---|---|
| AA-IFBenchSource | 45.4% | 67.3% | Step 3.7 Flash leads |
Frequently Asked Questions (2)
Which is better, Claude 4 Sonnet or Step 3.7 Flash?
Step 3.7 Flash is ahead on BenchLM's provisional leaderboard, 57 to 48.
Which is better for coding, Claude 4 Sonnet or Step 3.7 Flash?
Claude 4 Sonnet has the edge for coding in this comparison, averaging 72.7 versus 56.3. Inside this category, Terminal-Bench Hard is the benchmark that creates the most daylight between them.
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