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Radar

Five or fewer confirmed AI changes, with original sources, on mornings when something changed.A free source-linked morning brief.

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Model A
GPT-4.1 nano

OpenAI

28.43/100

Estimated · Public rank #223

90% interval 22.734.2

GPT-4.1 nano vs GPT-5.5 Pro

Updated September 4, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.

OpenAI logo
Model B
GPT-5.5 Pro

OpenAI

63.07/100

Estimated · Public rank #56

90% interval 51.674.6

Decision reading

GPT-5.5 Pro has the higher public score, 63.07 versus 28.43, and the 90% score intervals do not overlap.

1 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

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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.

  • Long documents

    Prompts that approach the documented context limit

    GPT-5.5 Pro

    GPT-5.5 Pro has the larger documented context window.

    Confidence: documented

  • Chat turn cost

    1K fresh input + 500 output tokens

    GPT-4.1 nano

    GPT-4.1 nano 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

    GPT-4.1 nano

    GPT-4.1 nano has the lower estimated token cost for this stated workload. GPT-4.1 nano has no published cached-input rate, so cached tokens use its listed input rate. GPT-5.5 Pro has no published cached-input rate, so cached tokens use its listed input rate.

    Confidence: rate-fallback

Show secondary and unsupported calls
  • Repository review cost

    50K fresh input + 3K output tokens

    GPT-4.1 nano

    GPT-4.1 nano has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates

  • Coding work

    Code generation, repair, and software-engineering tasks

    Not enough matched evidence

    GPT-5.5 Pro is not ranked on the public lane for coding, so no winner is named for coding.

    Confidence: limited

  • Agentic work

    Tool use, computer use, and multi-step task completion

    Not enough matched evidence

    GPT-4.1 nano and GPT-5.5 Pro are scored on Estimated evidence for agentic, so the reading is directional rather than like-for-like.

    Confidence: limited

What is actually comparable

Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.

Shared results
1
GPT-4.1 nano only
3
GPT-5.5 Pro only
5
Like-for-like categories
0 / 8

2 categories rest 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.

Agentic

Directional only
GPT-4.1 nano
32.0
Estimated · #137/151
GPT-5.5 Pro
60.6
Estimated · #24/151
Basis
BenchAlign lane · 0 vs 1 public rows
Reading
Directional only

Knowledge

Directional only
GPT-4.1 nano
30.2
Supported · #175/181
GPT-5.5 Pro
61.1
Estimated · #36/181
Basis
BenchAlign lane · 2 vs 2 public rows
Reading
Directional only

Coding

Not comparable
GPT-4.1 nano
32.3
Estimated · #164/183
GPT-5.5 Pro
Not ranked
Basis
BenchAlign lane · 0 vs 0 public rows
Reading
Not comparable

Reasoning

Not comparable
GPT-4.1 nano
34.9
Unranked · 2 rankable rows
GPT-5.5 Pro
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Math

Not comparable
GPT-4.1 nano
25.6
Unranked · 1 rankable row
GPT-5.5 Pro
70.2
Unranked · 3 rankable rows
Basis
Provisional lane · 1 vs 2 weighted rows
Reading
Not comparable

Multilingual

Not comparable
GPT-4.1 nano
Not ranked
GPT-5.5 Pro
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multimodal

Not comparable
GPT-4.1 nano
25.3
Unranked · 1 rankable row
GPT-5.5 Pro
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Instruction following

Not comparable
GPT-4.1 nano
36.0
#106/120
GPT-5.5 Pro
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
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

    GPT-4.1 nano: 1.034%GPT-5.5 Pro: 51.000%Normalized gap 50.0Shared source

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

GPT-4.1 nano
$0.0003
Fits in one request
GPT-5.5 Pro
$0.12
Fits in one request

GPT-4.1 nano has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

GPT-4.1 nano
$0.0062
Fits in one request
GPT-5.5 Pro
$2.04
Fits in one request

GPT-4.1 nano has the lower modeled cost

Costs use the listed standard API rates.

Cache-heavy agent loop

200K cached + 20K fresh input + 10K output tokens

GPT-4.1 nano
$0.026
Fits in one request
Cached input priced at the published list-input rate
GPT-5.5 Pro
$8.40
Fits in one request
Cached input priced at the published list-input rate

GPT-4.1 nano has the lower modeled cost

GPT-4.1 nano has no published cached-input rate, so cached tokens use its listed input rate. GPT-5.5 Pro has no published cached-input rate, so cached tokens use its listed input rate.

Specification differences

Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.

Cached-input rate

A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.

GPT-4.1 nano

Not published

GPT-5.5 Pro

Not published

OpenAI pricing

Provider availability

GPT-4.1 nano

Not sourced

GPT-5.5 Pro

Generally Available · OpenAI Responses API

OpenAI model catalog

Reasoning profile

GPT-4.1 nano

Non-Reasoning

GPT-5.5 Pro

Reasoning

Weight access

GPT-4.1 nano

Proprietary

GPT-5.5 Pro

Proprietary

License

GPT-4.1 nano

Proprietary

GPT-5.5 Pro

Proprietary

Release date

GPT-4.1 nano

2025-04-14

GPT-5.5 Pro

2026-04-23

If you already use one of these models
Deployment change
Both entries list OpenAI as the provider. Confirm endpoint, model ID, limits, and feature support before switching.
Quality signal
GPT-5.5 Pro has the higher public score, 63.07 versus 28.43, and the 90% score intervals do not overlap.
Workload cost
Repository review: $0.0062 vs $2.04. Cache-heavy agent loop: $0.026 vs $8.40.
Context tradeoff
GPT-5.5 Pro has the larger documented window (1.05M).

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 evidence9 rows

Agentic

  • BrowseComp

    GPT-4.1 nano
    GPT-5.5 Pro90.1%
    Source

    Not directly comparable

Knowledge

  • MMLU

    GPT-4.1 nano80.1%
    Source
    GPT-5.5 Pro

    Not directly comparable

  • GPQA

    GPT-4.1 nano50.3%
    Source
    GPT-5.5 Pro

    Not directly comparable

  • HLE

    GPT-4.1 nano
    GPT-5.5 Pro57.2%
    Source

    Not directly comparable

  • HLE w/o tools

    GPT-4.1 nano
    GPT-5.5 Pro43.1%
    Source

    Not directly comparable

Math

  • FrontierMath v2 (Tiers 1-3)

    Shared source
    GPT-4.1 nano1.034%
    GPT-5.5 Pro51.000%

    GPT-5.5 Pro leads this result

  • FrontierMath (legacy)

    GPT-4.1 nano
    GPT-5.5 Pro52.4%
    Source

    Not directly comparable

  • FrontierMath v2 (Tier 4)

    GPT-4.1 nano
    GPT-5.5 Pro39.600%
    Source

    Not directly comparable

Instruction following

  • IFEval

    GPT-4.1 nano83.2%
    Source
    GPT-5.5 Pro

    Not directly comparable

Frequently asked questions

Which is better, GPT-4.1 nano or GPT-5.5 Pro?

GPT-5.5 Pro has the higher public score, 63.07 versus 28.43, 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, GPT-4.1 nano or GPT-5.5 Pro?

GPT-5.5 Pro is not ranked on the public lane for coding, so no winner is named for coding.

Which is better for agentic tasks, GPT-4.1 nano or GPT-5.5 Pro?

GPT-5.5 Pro scores higher for agentic tasks on the public lane, 60.6 to 32. GPT-4.1 nano and GPT-5.5 Pro are 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.

Which costs less, GPT-4.1 nano or GPT-5.5 Pro?

For the stated presets, chat costs $0.0003 on GPT-4.1 nano and $0.12 on GPT-5.5 Pro; repository review costs $0.0062 and $2.04; the cache-heavy agent loop costs $0.026 and $8.40. GPT-4.1 nano has no published cached-input rate, so cached tokens use its listed input rate. GPT-5.5 Pro has no published cached-input rate, so cached tokens use its listed input rate.

Which has the larger context window, GPT-4.1 nano or GPT-5.5 Pro?

GPT-5.5 Pro has the larger documented context window: 1.05M, compared with 1M.

Related comparisons

Last updated September 4, 2026

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