Coding
Like-for-like- GPT-5.4 mini
- 42.9
- Supported · #125/183
- GPT-5.5
- 67.7
- Supported · #8/183
- Basis
- BenchAlign lane · 4 vs 9 public rows
- Reading
- GPT-5.5 leads
Five or fewer confirmed AI changes, with original sources, on mornings when something changed.A free source-linked morning brief.
See the free Radar BriefUpdated 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 62.63, and the 90% score intervals do not overlap.
19 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
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.
Code generation, repair, and software-engineering tasks
GPT-5.5
GPT-5.5 leads on the public coding lane, 67.7 to 42.9, with Supported evidence for both models and non-overlapping 90% intervals.
Confidence: stronger
Prompts that approach the documented context limit
GPT-5.5
GPT-5.5 has the larger documented context window.
Confidence: documented
1K fresh input + 500 output tokens
GPT-5.4 mini
GPT-5.4 mini has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
200K cached + 20K fresh input + 10K output tokens
GPT-5.4 mini
GPT-5.4 mini has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
50K fresh input + 3K output tokens
GPT-5.4 mini
GPT-5.4 mini has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Tool use, computer use, and multi-step task completion
Not enough matched evidence
GPT-5.4 mini is scored on Estimated evidence for agentic, so the reading is directional rather than like-for-like.
Confidence: limited
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
3 categories rest on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.
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.
| Category | GPT-5.4 mini | GPT-5.5 | Basis | Reading |
|---|---|---|---|---|
| Coding | 42.9Supported · #125/183 | 67.7Supported · #8/183 | Like-for-likeBenchAlign lane · 4 vs 9 public rows | GPT-5.5 leads |
| Knowledge | 56.3Supported · #53/181 | 73.3Supported · #7/181 | Like-for-likeBenchAlign lane · 5 vs 6 public rows | GPT-5.5 leads · intervals overlap |
| Agentic | 42.4Estimated · #113/151 | 63.9Supported · #15/151 | Directional onlyBenchAlign lane · 6 vs 13 public rows | Directional only |
| Multimodal | 57.2#31/48 | 71.3#19/48 | Directional onlyProvisional lane · 1 vs 2 weighted rows | Directional only |
| Instruction following | 89.6#23/120 | 92.9#7/120 | Directional onlyProvisional lane · 0 vs 0 weighted rows | Directional only |
| Reasoning | 73.5Unranked · 2 rankable rows | 63.5#15/22 | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Math | 44.5Unranked · 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 |
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.
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 (Tier 4)
Math
FrontierMath v2 (Tiers 1-3)
Math
Terminal-Bench 2.0
Agentic
HLE w/o tools
Knowledge
HLE
Knowledge
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.
1K fresh input + 500 output tokens
GPT-5.4 mini has the lower modeled cost
Costs use the listed standard API rates.
50K fresh input + 3K output tokens
GPT-5.4 mini has the lower modeled cost
Costs use the listed standard API rates.
200K cached + 20K fresh input + 10K output tokens
GPT-5.4 mini has the lower modeled cost
Costs use the listed standard API rates.
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
Maximum documented context; output-token limits may be lower.
GPT-5.4 mini
GPT-5.5
GPT-5.4 mini
gpt-5.4-mini
OpenAI GPT-5.4 mini model documentationGPT-5.5
gpt-5.5
OpenAI pricingA missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
GPT-5.4 mini
$0.075 per 1M cached input tokens
OpenAI pricingGPT-5.5
$0.5 per 1M cached input tokens
OpenAI pricingGPT-5.4 mini
text, image
OpenAI model catalogGPT-5.5
Not sourced
GPT-5.4 mini
GPT-5.5
Not sourced
GPT-5.4 mini
Generally Available · OpenAI Responses API
OpenAI model catalogGPT-5.5
Not sourced
GPT-5.4 mini
Reasoning
GPT-5.5
Reasoning
GPT-5.4 mini
Proprietary
GPT-5.5
Proprietary
GPT-5.4 mini
Proprietary
GPT-5.5
Proprietary
GPT-5.4 mini
2026-03-17
GPT-5.5
2026-04-23
Run the same representative tasks against both endpoints before changing production traffic.
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Terminal-Bench 2.0
GPT-5.5 leads this result
OSWorld-Verified
GPT-5.5 leads this result
MCP Atlas
GPT-5.5 leads this result
Toolathlon
GPT-5.5 leads this result
τ²-bench results
GPT-5.5 leads this result
Terminal-Bench 2.1 (Vals)
GPT-5.5 leads this result
CyberGym
Not directly comparable
BrowseComp
Not directly comparable
Gert Labs
Not directly comparable
ResearchClawBench
Not directly comparable
OSWorld 2.0
Not directly comparable
JobBench
Not directly comparable
ExploitGym
Not directly comparable
Vibe Code Bench
Shared sourceGPT-5.5 leads this result
FrontierCode 1.1 Main
Shared sourceGPT-5.5 leads this result
LiveCodeBench (Vals)
GPT-5.5 leads this result
SWE-bench (Vals)
GPT-5.5 leads this result
SWE-bench Pro
Not directly comparable
Terminal-Bench 2.0
Not directly comparable
React Native Evals
Not directly comparable
cursorBench31
Not directly comparable
cursorBench32
Not directly comparable
GPQA
GPT-5.5 leads this result
HLE
GPT-5.5 leads this result
HLE w/o tools
GPT-5.5 leads this result
GPQA Diamond (Vals)
GPT-5.5 leads this result
MMLU-Pro (Vals)
GPT-5.5 leads this result
GPQA-D
Not directly comparable
FrontierMath v2 (Tiers 1-3)
Shared sourceGPT-5.5 leads this result
FrontierMath v2 (Tier 4)
Shared sourceGPT-5.5 leads this result
FrontierMath (legacy)
Not directly comparable
GPT-5.5 has the higher public score, 73.27 versus 62.63, and the 90% score intervals do not overlap. That is the clearest overall quality signal in the current public data.
GPT-5.5 leads the public coding lane, 67.7 to 42.9, with Supported evidence for both models and non-overlapping 90% intervals.
GPT-5.5 scores higher for agentic tasks on the public lane, 63.9 to 42.4. GPT-5.4 mini is scored on Estimated evidence for agentic tasks, so the reading is directional rather than like-for-like. BenchLM does not name a winner for agentic tasks from a directional reading; read the shared benchmark rows directly and test the models on the same task set.
For the stated presets, chat costs $0.003 on GPT-5.4 mini and $0.02 on GPT-5.5; repository review costs $0.051 and $0.34; the cache-heavy agent loop costs $0.075 and $0.5. Costs use the listed standard API rates.
GPT-5.5 has the larger documented context window: 1M, compared with 400K.
Last updated September 4, 2026
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