Model comparison
Claude Haiku 4.5 vs Step 2 16k Exp 202412
Claude Haiku 4.5 and Step 2 16k Exp 202412 score almost the same on the Noometry Index (39.5 vs 39.2), so choose on price, context window or the category you care about most.
Last verified . 12 shared benchmarks.
StepFunSummary
- They share 12 benchmarks with published results for both. Claude Haiku 4.5 scores higher in 7 categories and Step 2 16k Exp 202412 in 1 category; 8 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Step 2 16k Exp 202412 leads 25.9 to 15.1.
Side by side
| Claude Haiku 4.5 | Step 2 16k Exp 202412 | |
|---|---|---|
| Provider | Anthropic | StepFun |
| Noometry Index | 39.5 | 39.2 |
| Released | 2025-10-15 | — |
| Weights | Proprietary | Proprietary |
| Context window | 200K | — |
| Max output | 64K | — |
| Input $ / M tokens | $1 | — |
| Output $ / M tokens | $5 | — |
| Results tracked | 53 | 12 |
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Category by category
Coding Claude Haiku 4.5 leads
Claude Haiku 4.5: 44.0 (#78), Step 2 16k Exp 202412: 38.5 (#174)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Coding | 1453 | 1316 |
| SWE-bench Verified (bash only) | 66.6% | — |
| LMArena WebDev | 1330 | — |
| SWE-bench Multilingual | 64.7% | — |
| SciCode | 43.3% | — |
| WeirdML | 45.4% | — |
| ALE-Bench | 653.48 | — |
Agentic & Tool Use Not comparable
Claude Haiku 4.5: 33.6 (#52), Step 2 16k Exp 202412: —
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| Terminal-Bench | 35.5% | — |
| Berkeley Function Calling Leaderboard | 68.7% | — |
| DeepResearch Bench | 45.5% | — |
| BALROG | 31.2% | — |
| ExploitBench | 13.7% | — |
| Vending-Bench 2 | 458.89 | — |
Reasoning Step 2 16k Exp 202412 leads
Claude Haiku 4.5: 15.1 (#320), Step 2 16k Exp 202412: 25.9 (#142)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Hard Prompts | 1420 | 1299 |
| ARC-AGI-2 | 4% | — |
| NYT Connections (extended) | 14.3% | — |
| ARC-AGI-1 | 47.7% | — |
| CritPt | 0% | — |
| Chess Puzzles | 8% | — |
| DTBench | 73.6% | — |
| LMCA | 30.9% | — |
| Epoch Capabilities Index | 142.41 | — |
| ForecastBench | 61.4 | — |
Math Claude Haiku 4.5 leads
Claude Haiku 4.5: 44.9 (#78), Step 2 16k Exp 202412: 36.3 (#169)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Math | 1396 | 1304 |
| OTIS Mock AIME 2024-2025 | 66.7% | — |
| Omni-MATH | 56.1% | — |
| MATH Level 5 | 96.4% | — |
| FrontierMath (Feb 2025 set) | 5.9% | — |
| FrontierMath Tier 4 (v1) | 2.1% | — |
Knowledge Claude Haiku 4.5 leads
Claude Haiku 4.5: 37.7 (#153), Step 2 16k Exp 202412: 35.2 (#187)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Expert | 1442 | 1279 |
| GPQA Diamond | 71.2% | — |
| SimpleQA Verified | 13.2% | — |
| MMLU-Pro | 77.7% | — |
| Vectara Hallucination Rate | 9.8% | — |
| GPQA (HELM) | 60.5% | — |
Multimodal Not comparable
Claude Haiku 4.5: 26.8 (#118), Step 2 16k Exp 202412: —
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| Blueprint-Bench 2 | 0% | — |
| LMArena Document | 1420 | — |
Multilingual Claude Haiku 4.5 leads
Claude Haiku 4.5: 49.9 (#129), Step 2 16k Exp 202412: 43.7 (#181)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Non-English | 1377 | 1290 |
| LMArena Chinese | 1417 | 1331 |
| LMArena Russian | 1381 | 1324 |
| LMArena French | 1408 | — |
| LMArena German | 1375 | — |
| LMArena Japanese | 1339 | — |
| LMArena Korean | 1347 | — |
| LMArena Spanish | 1420 | — |
Instruction Following Claude Haiku 4.5 leads
Claude Haiku 4.5: 71.4 (#149), Step 2 16k Exp 202412: 67.9 (#192)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Instruction Following | 1414 | 1287 |
| IFEval | 80.1% | — |
Long Context Claude Haiku 4.5 leads
Claude Haiku 4.5: 43.6 (#92), Step 2 16k Exp 202412: 39.7 (#170)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Longer Query | 1427 | 1307 |
Writing & Preference Claude Haiku 4.5 leads
Claude Haiku 4.5: 57.9 (#123), Step 2 16k Exp 202412: 52.3 (#173)
| Benchmark | Claude Haiku 4.5 | Step 2 16k Exp 202412 |
|---|---|---|
| LMArena Text | 1396 | 1321 |
| LMArena Creative Writing | 1372 | 1328 |
| LMArena Multi-Turn | 1409 | 1292 |
| WildBench | 83.9% | — |
| EQ-Bench 4 | 1064 | — |
Frequently asked questions
Is Claude Haiku 4.5 better than Step 2 16k Exp 202412?
Claude Haiku 4.5 and Step 2 16k Exp 202412 score almost the same on the Noometry Index (39.5 vs 39.2), so choose on price, context window or the category you care about most.
Is Claude Haiku 4.5 or Step 2 16k Exp 202412 better for coding?
Claude Haiku 4.5 scores higher on coding benchmarks: 44.0 versus 38.5 in the Noometry coding category.
How many benchmarks do Claude Haiku 4.5 and Step 2 16k Exp 202412 share?
12 benchmarks have published results for both models. Claude Haiku 4.5 has 53 scored results on Noometry and Step 2 16k Exp 202412 has 12.