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BenchLM
Model A
Claude Sonnet 4.5 Thinking

Anthropic

—

Evidence status unavailable

90% interval unavailable

Claude Sonnet 4.5 Thinking vs Gemini 3.5 Flash

Updated August 18, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.

Model B
Gemini 3.5 Flash

Google

64.7/100

Estimated · Public rank #39

90% interval 54.1–75.2

Decision reading

At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner.

1 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

    Gemini 3.5 Flash

    Gemini 3.5 Flash has the larger documented context window.

    Confidence: documented

Show secondary and unsupported calls

  • 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

    No shared weighted benchmark basis supports a winner.

    Confidence: limited

  • Chat turn cost

    1K fresh input + 500 output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    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 Sonnet 4.5 Thinking does not fit this workload in one request. Claude Sonnet 4.5 Thinking has no comparable published API token rate.

    Confidence: listed-rates

  • Repository review cost

    50K fresh input + 3K output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    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.

Shared results
1
Claude Sonnet 4.5 Thinking only
0
Gemini 3.5 Flash only
22
Like-for-like categories
0 / 8

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

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
77.2
Weighted basis
0 vs 2 rows
Reading
Not comparable

Coding

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
55.1
Weighted basis
0 vs 1 rows
Reading
Not comparable

Reasoning

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
74.7
Weighted basis
0 vs 2 rows
Reading
Not comparable

Knowledge

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
40.2
Weighted basis
0 vs 1 rows
Reading
Not comparable

Math

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
32.9
Weighted basis
0 vs 2 rows
Reading
Not comparable

Multilingual

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Multimodal

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
83.8
Weighted basis
0 vs 2 rows
Reading
Not comparable

Instruction following

Not comparable
Claude Sonnet 4.5 Thinking
Not measured
Gemini 3.5 Flash
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.

A shared-evidence shape is not available.

BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.

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 Sonnet 4.5 Thinking
API rate not published
Fits in one request
Gemini 3.5 Flash
$0.006
Fits in one request

Claude Sonnet 4.5 Thinking has no comparable published API token rate.

Repository review

50K fresh input + 3K output tokens

Claude Sonnet 4.5 Thinking
API rate not published
Fits in one request
Gemini 3.5 Flash
$0.102
Fits in one request

Claude Sonnet 4.5 Thinking has no comparable published API token rate.

Cache-heavy agent loop

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

Claude Sonnet 4.5 Thinking
API rate not published
Does not fit in one request
Cached-input rate unavailable
Gemini 3.5 Flash
$0.15
Fits in one request

Claude Sonnet 4.5 Thinking does not fit this workload in one request. Claude Sonnet 4.5 Thinking has no comparable published API token rate.

Specification differences

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

Context window

Maximum documented context; output-token limits may be lower.

Claude Sonnet 4.5 Thinking

200K

Gemini 3.5 Flash

1M

Google Gemini API pricing

Cached-input rate

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

Claude Sonnet 4.5 Thinking

No comparable hosted API rate

Gemini 3.5 Flash

$0.15 per 1M cached input tokens

Google Gemini API pricing

Documented inputs

Claude Sonnet 4.5 Thinking

Not sourced

Gemini 3.5 Flash

Not sourced

Documented outputs

Claude Sonnet 4.5 Thinking

Not sourced

Gemini 3.5 Flash

Not sourced

Provider availability

Claude Sonnet 4.5 Thinking

Not sourced

Gemini 3.5 Flash

Not sourced

Reasoning profile

Claude Sonnet 4.5 Thinking

Reasoning

Gemini 3.5 Flash

Reasoning

Weight access

Claude Sonnet 4.5 Thinking

Proprietary

Gemini 3.5 Flash

Proprietary

License

Claude Sonnet 4.5 Thinking

Proprietary

Gemini 3.5 Flash

Proprietary

Release date

Claude Sonnet 4.5 Thinking

2025-09-01

Gemini 3.5 Flash

2026-05-19

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
At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner.
Workload cost
A complete comparable API-rate estimate is not available for both models.
Context tradeoff
Gemini 3.5 Flash 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 evidence23 rows

Agentic

  • Terminal-Bench 2.0

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash76.2%
    Source

    Not directly comparable

  • MCP Atlas

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash83.6%
    Source

    Not directly comparable

  • Toolathlon

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash56.5%
    Source

    Not directly comparable

  • OSWorld-Verified

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash78.4%
    Source

    Not directly comparable

  • Finance Agent v2

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash57.9%
    Source

    Not directly comparable

  • Gert Labs

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash61.85%
    Source

    Not directly comparable

  • ResearchClawBench

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash18.0%
    Source

    Not directly comparable

Coding

  • Vibe Code Bench

    Shared source
    Claude Sonnet 4.5 Thinking22.62%
    Gemini 3.5 Flash48.68%

    Gemini 3.5 Flash leads this result

  • Terminal-Bench 2.0

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash76.2%
    Source

    Not directly comparable

  • SWE-bench Pro

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash55.1%
    Source

    Not directly comparable

  • cursorBench31

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash49.8%
    Source

    Not directly comparable

  • cursorBench32

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash48.8%
    Source

    Not directly comparable

  • EEBench

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash34.3%
    Source

    Not directly comparable

Reasoning

  • MRCRv2

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash77.3%
    Source

    Not directly comparable

  • MRCR 1M

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash26.6%
    Source

    Not directly comparable

  • ARC-AGI-2

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash72.1%
    Source

    Not directly comparable

Knowledge

  • GPQA-D

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash92.7%
    Source

    Not directly comparable

  • HLE

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash40.2%
    Source

    Not directly comparable

Math

  • FrontierMath v2 (Tiers 1-3)

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash38.966%
    Source

    Not directly comparable

  • FrontierMath v2 (Tier 4)

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash14.583%
    Source

    Not directly comparable

Multimodal

  • CharXiv

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash84.2%
    Source

    Not directly comparable

  • MMMU-Pro

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash83.6%
    Source

    Not directly comparable

  • Blueprint-Bench 2

    Claude Sonnet 4.5 Thinking—
    Gemini 3.5 Flash33.6%
    Source

    Not directly comparable

Frequently asked questions

Which is better, Claude Sonnet 4.5 Thinking or Gemini 3.5 Flash?

At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner. The page therefore keeps the decision tied to the specific documented workload.

Which is better for coding, Claude Sonnet 4.5 Thinking or Gemini 3.5 Flash?

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, Claude Sonnet 4.5 Thinking or Gemini 3.5 Flash?

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

Which costs less, Claude Sonnet 4.5 Thinking or Gemini 3.5 Flash?

Both models do not have comparable published API token rates, so this page does not name a universal price winner.

Which has the larger context window, Claude Sonnet 4.5 Thinking or Gemini 3.5 Flash?

Gemini 3.5 Flash has the larger documented context window: 1M, compared with 200K.

Related comparisons

Compare API pricing Read the methodology Open the model selector

Last updated August 18, 2026

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