Agentic
Like-for-like- Claude Haiku 4.5
- 27.0
- Supported · #143/151
- GPT-5.5
- 63.9
- Supported · #15/151
- Basis
- BenchAlign lane · 2 vs 13 public rows
- Reading
- GPT-5.5 leads
Claude Haiku 4.5 vs GPT-5.5
Updated September 4, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
GPT-5.5 has the higher public score, 73.27 versus 52.73, and the 90% score intervals do not overlap.
8 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
Share or export
Which one for your work
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
Coding work
Code generation, repair, and software-engineering tasks
GPT-5.5
GPT-5.5 leads on the public coding lane, 67.7 to 27.3, with Supported evidence for both models and non-overlapping 90% intervals.
Confidence: stronger
Agentic work
Tool use, computer use, and multi-step task completion
GPT-5.5
GPT-5.5 leads on the public agentic lane, 63.9 to 27, with Supported evidence for both models and non-overlapping 90% intervals.
Confidence: stronger
Long documents
Prompts that approach the documented context limit
GPT-5.5
GPT-5.5 has the larger documented context window.
Confidence: documented
Show secondary and unsupported calls
Chat turn cost
1K fresh input + 500 output tokens
Claude Haiku 4.5
Claude Haiku 4.5 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Repository review cost
50K fresh input + 3K output tokens
Claude Haiku 4.5
Claude Haiku 4.5 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Not enough matched evidence
The page does not recommend a cost winner because at least one model cannot fit the stated workload in one request. Claude Haiku 4.5 does not fit this workload in one request.
Confidence: listed-rates
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
2 Claude Haiku 4.5 only
8 Shared
30 GPT-5.5 only
- Shared results
- 8
- Claude Haiku 4.5 only
- 2
- GPT-5.5 only
- 30
- Like-for-like categories
- 2 / 8
1 category rests on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.
Category results, on a stated basis
Each row shows the public-lane category score for both models: the BenchAlign lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.
Coding
Like-for-like- Claude Haiku 4.5
- 27.3
- Supported · #173/183
- GPT-5.5
- 67.7
- Supported · #8/183
- Basis
- BenchAlign lane · 4 vs 9 public rows
- Reading
- GPT-5.5 leads
Knowledge
Directional only- Claude Haiku 4.5
- 44.6
- Estimated · #117/181
- GPT-5.5
- 73.3
- Supported · #7/181
- Basis
- BenchAlign lane · 2 vs 6 public rows
- Reading
- Directional only
Reasoning
Not comparable- Claude Haiku 4.5
- Not ranked
- GPT-5.5
- 63.5
- #15/22
- Basis
- Provisional lane · 0 vs 2 weighted rows
- Reading
- Not comparable
Math
Not comparable- Claude Haiku 4.5
- 28.9
- Unranked · 2 rankable rows
- GPT-5.5
- 69.6
- Unranked · 3 rankable rows
- Basis
- Provisional lane · 2 vs 2 weighted rows
- Reading
- Not comparable
Multilingual
Not comparable- Claude Haiku 4.5
- Not ranked
- GPT-5.5
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Claude Haiku 4.5
- Not ranked
- GPT-5.5
- 71.3
- #19/48
- Basis
- Provisional lane · 0 vs 2 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Claude Haiku 4.5
- Not ranked
- GPT-5.5
- 92.9
- #7/120
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
| Category | Claude Haiku 4.5 | GPT-5.5 | Basis | Reading |
|---|---|---|---|---|
| Agentic | 27.0Supported · #143/151 | 63.9Supported · #15/151 | Like-for-likeBenchAlign lane · 2 vs 13 public rows | GPT-5.5 leads |
| Coding | 27.3Supported · #173/183 | 67.7Supported · #8/183 | Like-for-likeBenchAlign lane · 4 vs 9 public rows | GPT-5.5 leads |
| Knowledge | 44.6Estimated · #117/181 | 73.3Supported · #7/181 | Directional onlyBenchAlign lane · 2 vs 6 public rows | Directional only |
| Reasoning | Not ranked | 63.5#15/22 | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Math | 28.9Unranked · 2 rankable rows | 69.6Unranked · 3 rankable rows | Not comparableProvisional lane · 2 vs 2 weighted rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | Not ranked | 71.3#19/48 | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Instruction following | Not ranked | 92.9#7/120 | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign) differ from the provisional-lane categories. Unranked scores sit on the lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.
Shape of the matched evidence
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
FrontierMath v2 (Tiers 1-3)
Math
LiveCodeBench (Vals)
Coding
FrontierMath v2 (Tier 4)
Math
MMLU-Pro (Vals)
Knowledge
What each workload costs
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
Chat turn
1K fresh input + 500 output tokens
- Claude Haiku 4.5
- $0.0035
- Fits in one request
- GPT-5.5
- $0.02
- Fits in one request
Claude Haiku 4.5 has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Claude Haiku 4.5
- $0.065
- Fits in one request
- GPT-5.5
- $0.34
- Fits in one request
Claude Haiku 4.5 has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Claude Haiku 4.5
- $0.09
- Does not fit in one request
- GPT-5.5
- $0.5
- Fits in one request
Claude Haiku 4.5 does not fit this workload in one request.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationClaude Haiku 4.5GPT-5.5
Context window
Maximum documented context; output-token limits may be lower.
Claude Haiku 4.5
GPT-5.5
API model ID
Claude Haiku 4.5
claude-haiku-4-5-20251001
Claude API pricingGPT-5.5
gpt-5.5
OpenAI pricingCached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Claude Haiku 4.5
$0.1 per 1M cached input tokens
Claude API pricingGPT-5.5
$0.5 per 1M cached input tokens
OpenAI pricingDocumented inputs
Claude Haiku 4.5
Not sourced
GPT-5.5
Not sourced
Documented outputs
Claude Haiku 4.5
Not sourced
GPT-5.5
Not sourced
Provider availability
Claude Haiku 4.5
Not sourced
GPT-5.5
Not sourced
Reasoning profile
Claude Haiku 4.5
Non-Reasoning
GPT-5.5
Reasoning
Weight access
Claude Haiku 4.5
Proprietary
GPT-5.5
Proprietary
License
Claude Haiku 4.5
Proprietary
GPT-5.5
Proprietary
Release date
Claude Haiku 4.5
2025-10-15
GPT-5.5
2026-04-23
If you already use one of these models
- Deployment change
- The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
- Quality signal
- GPT-5.5 has the higher public score, 73.27 versus 52.73, and the 90% score intervals do not overlap.
- Workload cost
- Repository review: $0.065 vs $0.34. Cache-heavy agent loop: $0.09 vs $0.5.
- Context tradeoff
- GPT-5.5 has the larger documented window (1M).
Run the same representative tasks against both endpoints before changing production traffic.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence40 rows
Agentic
JobBench
Shared sourceClaude Haiku 4.516.0%GPT-5.542.7%GPT-5.5 leads this result
Terminal-Bench 2.1 (Vals)
Claude Haiku 4.543.8%SourceGPT-5.576.4%SourceGPT-5.5 leads this result
Terminal-Bench 2.0
Claude Haiku 4.5—GPT-5.582%SourceNot directly comparable
CyberGym
Claude Haiku 4.5—GPT-5.581.8%SourceNot directly comparable
BrowseComp
Claude Haiku 4.5—GPT-5.584.4%SourceNot directly comparable
OSWorld-Verified
Claude Haiku 4.5—GPT-5.578.7%SourceNot directly comparable
MCP Atlas
Claude Haiku 4.5—GPT-5.575.3%SourceNot directly comparable
Toolathlon
Claude Haiku 4.5—GPT-5.555.6%SourceNot directly comparable
τ²-bench results
Claude Haiku 4.5—GPT-5.598%SourceNot directly comparable
Gert Labs
Claude Haiku 4.5—GPT-5.572.93%SourceNot directly comparable
ResearchClawBench
Claude Haiku 4.5—GPT-5.517.0%SourceNot directly comparable
OSWorld 2.0
Claude Haiku 4.5—GPT-5.513.0%SourceNot directly comparable
ExploitGym
Claude Haiku 4.5—GPT-5.513.4%SourceNot directly comparable
Coding
SWE-bench Verified
Claude Haiku 4.573.3%SourceGPT-5.5—Not directly comparable
VulcanBench v3
Claude Haiku 4.576.2%SourceGPT-5.5—Not directly comparable
LiveCodeBench (Vals)
Claude Haiku 4.541.2%SourceGPT-5.585.3%SourceGPT-5.5 leads this result
SWE-bench (Vals)
Claude Haiku 4.566.6%SourceGPT-5.582.6%SourceGPT-5.5 leads this result
SWE-bench Pro
Claude Haiku 4.5—GPT-5.558.6%SourceNot directly comparable
Terminal-Bench 2.0
Claude Haiku 4.5—GPT-5.582.0%SourceNot directly comparable
Vibe Code Bench
Claude Haiku 4.5—GPT-5.569.85%SourceNot directly comparable
React Native Evals
Claude Haiku 4.5—GPT-5.584.7%SourceNot directly comparable
cursorBench31
Claude Haiku 4.5—GPT-5.559.2%SourceNot directly comparable
cursorBench32
Claude Haiku 4.5—GPT-5.558.4%SourceNot directly comparable
FrontierCode 1.1 Main
Claude Haiku 4.5—GPT-5.543.0%SourceNot directly comparable
Reasoning
Knowledge
GPQA Diamond (Vals)
Claude Haiku 4.572.2%SourceGPT-5.593.2%SourceGPT-5.5 leads this result
MMLU-Pro (Vals)
Claude Haiku 4.578.7%SourceGPT-5.588.1%SourceGPT-5.5 leads this result
GPQA
Claude Haiku 4.5—GPT-5.593.6%SourceNot directly comparable
GPQA-D
Claude Haiku 4.5—GPT-5.593.6%SourceNot directly comparable
HLE
Claude Haiku 4.5—GPT-5.552.2%SourceNot directly comparable
HLE w/o tools
Claude Haiku 4.5—GPT-5.541.4%SourceNot directly comparable
Math
FrontierMath v2 (Tiers 1-3)
Shared sourceClaude Haiku 4.55.903%GPT-5.551.700%GPT-5.5 leads this result
FrontierMath v2 (Tier 4)
Shared sourceClaude Haiku 4.52.083%GPT-5.535.400%GPT-5.5 leads this result
FrontierMath (legacy)
Claude Haiku 4.5—GPT-5.551.7%SourceNot directly comparable
Multimodal
Frequently asked questions
Which is better, Claude Haiku 4.5 or GPT-5.5?
GPT-5.5 has the higher public score, 73.27 versus 52.73, and the 90% score intervals do not overlap. That is the clearest overall quality signal in the current public data.
Which is better for coding, Claude Haiku 4.5 or GPT-5.5?
GPT-5.5 leads the public coding lane, 67.7 to 27.3, with Supported evidence for both models and non-overlapping 90% intervals.
Which is better for agentic tasks, Claude Haiku 4.5 or GPT-5.5?
GPT-5.5 leads the public agentic tasks lane, 63.9 to 27, with Supported evidence for both models and non-overlapping 90% intervals.
Which costs less, Claude Haiku 4.5 or GPT-5.5?
For the stated presets, chat costs $0.0035 on Claude Haiku 4.5 and $0.02 on GPT-5.5; repository review costs $0.065 and $0.34; the cache-heavy agent loop costs $0.09 and $0.5. Claude Haiku 4.5 does not fit this workload in one request.
Which has the larger context window, Claude Haiku 4.5 or GPT-5.5?
GPT-5.5 has the larger documented context window: 1M, compared with 200K.
Related comparisons
Last updated September 4, 2026
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