Model comparison
Claude 3.5 Sonnet vs Claude Haiku 4.5
Head-to-head evidence from 3 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude 3.5 Sonnet #132 (Estimated); Claude Haiku 4.5 #77 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude 3.5 Sonnet and Claude Haiku 4.5 share 3 comparable benchmark results. 2 of 8 categories are comparable. 1 result is unique to Claude 3.5 Sonnet; 2 to Claude Haiku 4.5.
Updated July 20, 2026- Shared results
- 3
- Claude 3.5 Sonnet only
- 1
- Claude Haiku 4.5 only
- 2
- Comparable categories
- 2 / 8
Pick Claude Haiku 4.5 if you want the stronger benchmark profile. Claude 3.5 Sonnet only becomes the better choice if its workflow or ecosystem matters more than the raw scoreboard.
Confidence note. This is a partial-evidence comparison with 3 shared benchmark results across 2 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Haiku 4.5 is clearly ahead on the BenchAlign aggregate, 56.58 to 47.74. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Haiku 4.5's sharpest advantage is in coding, where it averages 73.3 against 49. The single biggest benchmark swing on the page is SWE-bench Verified, 49% to 73.3%.
Claude 3.5 Sonnet is also the more expensive model on tokens at $3.00 input / $15.00 output per 1M tokens, versus $1.00 input / $5.00 output per 1M tokens for Claude Haiku 4.5. That is roughly 3.0x on output cost alone.
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 3.5 Sonnet | Δ | Claude Haiku 4.5 |
|---|---|---|---|
| Coding | Claude 3.5 Sonnet49.0 | Margin→ 24.3 | Claude Haiku 4.573.3 |
| Math | Claude 3.5 Sonnet1.6 | Margin→ 3.3 | Claude Haiku 4.54.9 |
| Knowledge | Claude 3.5 Sonnet59.4 | MarginNo overlap | Claude Haiku 4.5Not measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Verified
CodingA 49%B 73.3%Winner: Claude Haiku 4.5Δ 24.3SWE-bench Verified: Claude 3.5 Sonnet scored 49%; Claude Haiku 4.5 scored 73.3%. Claude Haiku 4.5 wins this benchmark. - Source ↗
FrontierMath v2 (Tiers 1-3)
MathA 2.069%B 5.903%Winner: Claude Haiku 4.5Δ 3.8FrontierMath v2 (Tiers 1-3): Claude 3.5 Sonnet scored 2.069%; Claude Haiku 4.5 scored 5.903%. Claude Haiku 4.5 wins this benchmark. - Source ↗
FrontierMath v2 (Tier 4)
MathA 0.000%B 2.083%Winner: Claude Haiku 4.5Δ 2.1FrontierMath v2 (Tier 4): Claude 3.5 Sonnet scored 0.000%; Claude Haiku 4.5 scored 2.083%. Claude Haiku 4.5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude 3.5 Sonnet | Claude Haiku 4.5 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude 3.5 Sonnet$3 input / $15 output | Claude Haiku 4.5$1 input / $5 output | Claude Haiku 4.5 has the lower combined listed price. |
| Generation speedtokens per second | Claude 3.5 SonnetNot available | Claude Haiku 4.5Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude 3.5 SonnetNot available | Claude Haiku 4.5Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude 3.5 Sonnet200K | Claude Haiku 4.5200K | Listed context windows are equal. |
Benchmark Deep Dive
Agentic1 benchmarks
| Benchmark | Claude 3.5 Sonnet | Claude Haiku 4.5 | Result |
|---|---|---|---|
| JobBenchSource | — | 16.0% | Not comparable |
CodingClaude Haiku 4.5 wins1 benchmarks
| Benchmark | Claude 3.5 Sonnet | Claude Haiku 4.5 | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 49% | 73.3% | Claude Haiku 4.5 leads |
Knowledge1 benchmarks
| Benchmark | Claude 3.5 Sonnet | Claude Haiku 4.5 | Result |
|---|---|---|---|
| GPQASource | 59.4% | — | Not comparable |
MathClaude Haiku 4.5 wins2 benchmarks
Multimodal1 benchmarks
| Benchmark | Claude 3.5 Sonnet | Claude Haiku 4.5 | Result |
|---|---|---|---|
| Design Arena WebsiteSource | — | 1154 | Not comparable |
Frequently Asked Questions (3)
Which is better, Claude 3.5 Sonnet or Claude Haiku 4.5?
Claude Haiku 4.5 is ahead on BenchLM's BenchAlign leaderboard, 56.58 to 47.74. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 49% and 73.3%.
Which is better for coding, Claude 3.5 Sonnet or Claude Haiku 4.5?
Claude Haiku 4.5 has the edge for coding in this comparison, averaging 73.3 versus 49. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
Which is better for math, Claude 3.5 Sonnet or Claude Haiku 4.5?
Claude Haiku 4.5 has the edge for math in this comparison, averaging 4.9 versus 1.6. Inside this category, FrontierMath v2 (Tiers 1-3) is the benchmark that creates the most daylight between them.
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