Model comparison
Claude Haiku 4.5 vs Claude Sonnet 5
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: Claude Haiku 4.5 #77 (Estimated); Claude Sonnet 5 #29 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Haiku 4.5 and Claude Sonnet 5 share 2 comparable benchmark results. 1 of 8 categories are comparable. 3 results are unique to Claude Haiku 4.5; 34 to Claude Sonnet 5.
Updated July 23, 2026- Shared results
- 2
- Claude Haiku 4.5 only
- 3
- Claude Sonnet 5 only
- 34
- Comparable categories
- 1 / 8
Pick Claude Sonnet 5 if you want the stronger benchmark profile. Claude Haiku 4.5 only becomes the better choice if you want the cheaper token bill or you would rather avoid the extra latency and token burn of a reasoning model.
Confidence note. This is a partial-evidence comparison with 2 shared benchmark results across 2 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
Claude Sonnet 5 is clearly ahead on the BenchAlign aggregate, 65.32 to 56.58. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Sonnet 5's sharpest advantage is in coding, where it averages 76.7 against 73.3. The single biggest benchmark swing on the page is SWE-bench Verified, 73.3% to 85.2%.
Claude Sonnet 5 is also the more expensive model on tokens at $2.00 input / $10.00 output per 1M tokens, versus $1.00 input / $5.00 output per 1M tokens for Claude Haiku 4.5. That is roughly 2.0x on output cost alone. Claude Sonnet 5 is the reasoning model in the pair, while Claude Haiku 4.5 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. Claude Sonnet 5 gives you the larger context window at 1M, compared with 200K for Claude Haiku 4.5.
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 Haiku 4.5 | Δ | Claude Sonnet 5 |
|---|---|---|---|
| Coding | Claude Haiku 4.573.3 | Margin→ 3.4 | Claude Sonnet 576.7 |
| Agentic | Claude Haiku 4.5Not measured | MarginNo overlap | Claude Sonnet 581.9 |
| Knowledge | Claude Haiku 4.5Not measured | MarginNo overlap | Claude Sonnet 557.4 |
| Math | Claude Haiku 4.54.9 | MarginNo overlap | Claude Sonnet 5Not measured |
| Multimodal | Claude Haiku 4.5Not measured | MarginNo overlap | Claude Sonnet 588.3 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Verified
CodingA 73.3%B 85.2%Winner: Claude Sonnet 5Δ 11.9SWE-bench Verified: Claude Haiku 4.5 scored 73.3%; Claude Sonnet 5 scored 85.2%. Claude Sonnet 5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Haiku 4.5 | Claude Sonnet 5 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Haiku 4.5$1 input / $5 output | Claude Sonnet 5$2 input / $10 output | Claude Haiku 4.5 has the lower combined listed price. |
| Generation speedtokens per second | Claude Haiku 4.5Not available | Claude Sonnet 5Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Haiku 4.5Not available | Claude Sonnet 5Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Haiku 4.5200K | Claude Sonnet 51M | Claude Sonnet 5 lists the larger context window. |
Benchmark Deep Dive
Agentic14 benchmarks
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5 | Result |
|---|---|---|---|
| JobBenchSource | 16.0% | — | Not comparable |
| Terminal-Bench 2.0Source | — | 80.4% | Not comparable |
| BrowseCompSource | — | 84.7% | Not comparable |
| HLE w/ toolsSource | — | 57.4% | Not comparable |
| OSWorld-VerifiedSource | — | 81.2% | Not comparable |
| GDPval-AASource | — | 1607 | Not comparable |
| AA Agentic IndexSource | — | 46.7% | Not comparable |
| GDPval-AASource | — | 55.4% | Not comparable |
| AA BriefcaseSource | — | 1388 | Not comparable |
| AA AutomationBenchSource | — | 39.2% | Not comparable |
| AA EnterpriseOps-GymSource | — | 44.7% | Not comparable |
| AA Harvey LABSource | — | 90.1% | Not comparable |
| AA Tau3 BankingSource | — | 28.2% | Not comparable |
| aaTerminalBench21Source | — | 80.5% | Not comparable |
CodingClaude Sonnet 5 wins9 benchmarks
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5 | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 73.3% | 85.2% | Claude Sonnet 5 leads |
| SWE-bench ProSource | — | 63.2% | Not comparable |
| SWE MultilingualSource | — | 78.3% | Not comparable |
| SWE MultimodalSource | — | 28.1% | Not comparable |
| Terminal-Bench 2.0Source | — | 80.4% | Not comparable |
| FrontierCode 1.1 MainSource | — | 42.7% | Not comparable |
| cursorBench32Source | — | 61.5% | Not comparable |
| AA Coding IndexSource | — | 71.5% | Not comparable |
| AA-SciCodeSource | — | 53.6% | Not comparable |
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | Claude Haiku 4.5 | Claude Sonnet 5 | Result |
|---|---|---|---|
| HLESource | — | 57.4% | Not comparable |
| HLE w/o toolsSource | — | 43.2% | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 53.4% | Not comparable |
| AA-GPQA DiamondSource | — | 91.1% | Not comparable |
| AA-HLESource | — | 39.6% | Not comparable |
| AA-Omniscience IndexSource | — | 15.3% | Not comparable |
| AA-Omniscience AccuracySource | — | 38.3% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 37.3% | Not comparable |
Math2 benchmarks
Frequently Asked Questions (2)
Which is better, Claude Haiku 4.5 or Claude Sonnet 5?
Claude Sonnet 5 is ahead on BenchLM's BenchAlign leaderboard, 65.32 to 56.58. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 73.3% and 85.2%.
Which is better for coding, Claude Haiku 4.5 or Claude Sonnet 5?
Claude Sonnet 5 has the edge for coding in this comparison, averaging 76.7 versus 73.3. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
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