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Model comparison

GPT-5.4 mini vs Grok 4.20

Updated July 30, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.

GPT-5.4 mini

OpenAI

55.8/100

Estimated · Public rank #81

90% interval 44.3–67.3

Grok 4.20

xAI

53.9/100

Estimated · Public rank #93

90% interval 37.1–70.6

GPT-5.4 mini has the higher public score estimate, 55.79 versus 53.88, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.

4 results are shared. Category rows based on different benchmark sets are marked directional and do not name a winner.

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

    Grok 4.20

    Grok 4.20 has the larger documented context window.

    Confidence: documented

  • Chat turn cost

    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

  • Cache-heavy agent loop cost

    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. Grok 4.20 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-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

  • Coding work

    Code generation, repair, and software-engineering tasks

    Not enough matched evidence

    No shared weighted benchmark basis supports a winner.

    Confidence: limited

  • Agentic work

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

    Not enough matched evidence

    The category averages use different weighted benchmark sets, so they are 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
4
GPT-5.4 mini only
10
Grok 4.20 only
14
Like-for-like categories
0 / 8

2 categories use different evidence sets. Those rows remain visible for coverage context but do not name a winner.

Category results, on a stated basis

Each row states whether both averages use the same weighted benchmark set. Directional and not-comparable rows remain visible, but they never receive a winner in this template.

Agentic

Directional only
GPT-5.4 mini
65.7
Grok 4.20
47.1
Weighted basis
2 vs 1 rows
Reading
Directional only

Multimodal

Directional only
GPT-5.4 mini
76.6
Grok 4.20
70.1
Weighted basis
1 vs 2 rows
Reading
Directional only

Coding

Not comparable
GPT-5.4 mini
Not measured
Grok 4.20
67.1
Weighted basis
0 vs 2 rows
Reading
Not comparable

Reasoning

Not comparable
GPT-5.4 mini
Not measured
Grok 4.20
53.3
Weighted basis
0 vs 1 rows
Reading
Not comparable

Knowledge

Not comparable
GPT-5.4 mini
47.8
Grok 4.20
Not measured
Weighted basis
2 vs 0 rows
Reading
Not comparable

Math

Not comparable
GPT-5.4 mini
21.7
Grok 4.20
Not measured
Weighted basis
2 vs 0 rows
Reading
Not comparable

Multilingual

Not comparable
GPT-5.4 mini
Not measured
Grok 4.20
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Instruction following

Not comparable
GPT-5.4 mini
Not measured
Grok 4.20
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

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.

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-5.4 mini
$0.003
Fits in one request
Grok 4.20
$0.005
Fits in one request

GPT-5.4 mini has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

GPT-5.4 mini
$0.051
Fits in one request
Grok 4.20
$0.118
Fits in one request

GPT-5.4 mini 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-5.4 mini
$0.075
Fits in one request
Grok 4.20
$0.5
Fits in one request
Cached input priced at the published list-input rate

GPT-5.4 mini has the lower modeled cost

Grok 4.20 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-5.4 mini

$0.075 per 1M cached input tokens

OpenAI pricing

Grok 4.20

Not published

Provider availability

GPT-5.4 mini

Generally Available · OpenAI Responses API

OpenAI model catalog

Grok 4.20

Not sourced

Reasoning profile

GPT-5.4 mini

Reasoning

Grok 4.20

Reasoning

Weight access

GPT-5.4 mini

Proprietary

Grok 4.20

Proprietary

License

GPT-5.4 mini

Proprietary

Grok 4.20

Proprietary

Release date

GPT-5.4 mini

2026-03-17

Grok 4.20

2026-03-10

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-5.4 mini has the higher public score estimate, 55.79 versus 53.88, but the 90% score intervals overlap.
Workload cost
Repository review: $0.051 vs $0.118. Cache-heavy agent loop: $0.075 vs $0.5.
Context tradeoff
Grok 4.20 has the larger documented window (2M).

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 evidence28 rows

Agentic

  • Terminal-Bench 2.0

    GPT-5.4 mini60%
    Source
    Grok 4.2047.1%
    Source

    GPT-5.4 mini leads this result

  • OSWorld-Verified

    GPT-5.4 mini72.1%
    Source
    Grok 4.20—

    Not directly comparable

  • MCP Atlas

    GPT-5.4 mini57.7%
    Source
    Grok 4.20—

    Not directly comparable

  • Toolathlon

    GPT-5.4 mini42.9%
    Source
    Grok 4.20—

    Not directly comparable

  • τ²-bench results

    GPT-5.4 mini93.4%
    Source
    Grok 4.20—

    Not directly comparable

  • DeepSearchQA

    GPT-5.4 mini—
    Grok 4.2062.8%
    Source

    Not directly comparable

  • Gert Labs

    GPT-5.4 mini—
    Grok 4.2038.36%
    Source

    Not directly comparable

Coding

  • Vibe Code Bench

    Shared source
    GPT-5.4 mini47.97%
    Grok 4.204.06%

    GPT-5.4 mini leads this result

  • FrontierCode 1.1 Main

    GPT-5.4 mini27.0%
    Source
    Grok 4.20—

    Not directly comparable

  • LiveCodeBench Pro

    GPT-5.4 mini—
    Grok 4.2074.2%
    Source

    Not directly comparable

  • SWE-bench Verified

    GPT-5.4 mini—
    Grok 4.2076.7%
    Source

    Not directly comparable

  • SWE-bench Pro

    GPT-5.4 mini—
    Grok 4.2051.8%
    Source

    Not directly comparable

Reasoning

  • ARC-AGI-2

    GPT-5.4 mini—
    Grok 4.2053.3%
    Source

    Not directly comparable

  • ARC-AGI-3

    GPT-5.4 mini—
    Grok 4.200.1%
    Source

    Not directly comparable

Knowledge

  • GPQA

    GPT-5.4 mini88%
    Source
    Grok 4.20—

    Not directly comparable

  • HLE

    GPT-5.4 mini41.5%
    Source
    Grok 4.20—

    Not directly comparable

  • HLE w/o tools

    GPT-5.4 mini28.2%
    Source
    Grok 4.2031.6%
    Source

    Grok 4.20 leads this result

  • GPQA-D

    GPT-5.4 mini—
    Grok 4.2088.5%
    Source

    Not directly comparable

  • HealthBench Hard

    GPT-5.4 mini—
    Grok 4.2020.3%
    Source

    Not directly comparable

  • MedXpertQA (Text)

    GPT-5.4 mini—
    Grok 4.2050.2%
    Source

    Not directly comparable

Math

  • FrontierMath v2 (Tiers 1-3)

    GPT-5.4 mini28.280%
    Source
    Grok 4.20—

    Not directly comparable

  • FrontierMath v2 (Tier 4)

    GPT-5.4 mini2.080%
    Source
    Grok 4.20—

    Not directly comparable

Multimodal

  • MMMU-Pro

    GPT-5.4 mini76.6%
    Source
    Grok 4.2075.2%
    Source

    GPT-5.4 mini leads this result

  • MMMU-Pro w/ Python

    GPT-5.4 mini78%
    Source
    Grok 4.20—

    Not directly comparable

  • CharXiv

    GPT-5.4 mini—
    Grok 4.2060.9%
    Source

    Not directly comparable

  • ERQA

    GPT-5.4 mini—
    Grok 4.2054.1%
    Source

    Not directly comparable

  • SimpleVQA

    GPT-5.4 mini—
    Grok 4.2057.4%
    Source

    Not directly comparable

  • MedXpertQA (MM)

    GPT-5.4 mini—
    Grok 4.2065.8%
    Source

    Not directly comparable

Frequently asked questions

Which is better, GPT-5.4 mini or Grok 4.20?

GPT-5.4 mini has the higher public score estimate, 55.79 versus 53.88, but the 90% score intervals overlap. The higher estimate is not a decisive winner because the uncertainty ranges overlap.

Which is better for coding, GPT-5.4 mini or Grok 4.20?

The published evidence does not provide a shared weighted coding basis for both models, so BenchLM does not name a coding winner.

Which is better for agentic tasks, GPT-5.4 mini or Grok 4.20?

The current agentic tasks averages use different weighted benchmark sets, so BenchLM does not name a winner from them. Read the shared benchmark rows directly and test the models on the same task set.

Which costs less, GPT-5.4 mini or Grok 4.20?

For the stated presets, chat costs $0.003 on GPT-5.4 mini and $0.005 on Grok 4.20; repository review costs $0.051 and $0.118; the cache-heavy agent loop costs $0.075 and $0.5. Grok 4.20 has no published cached-input rate, so cached tokens use its listed input rate.

Which has the larger context window, GPT-5.4 mini or Grok 4.20?

Grok 4.20 has the larger documented context window: 2M, compared with 400K.

Related comparisons

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Last updated July 30, 2026

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