Skip to main content
Radar

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

Start free brief
Model A
Claude 3.5 Sonnet

Anthropic

48.1/100

Estimated · Public rank #142

90% interval 36.6–59.6

Claude 3.5 Sonnet 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

Gemini 3.5 Flash has the higher public score estimate, 64.67 versus 48.11, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.

2 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

  • Chat turn cost

    1K fresh input + 500 output tokens

    Gemini 3.5 Flash

    Gemini 3.5 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates

Show secondary and unsupported calls
  • Repository review cost

    50K fresh input + 3K output tokens

    Gemini 3.5 Flash

    Gemini 3.5 Flash 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

    No shared weighted benchmark basis supports a winner.

    Confidence: limited

  • 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 3.5 Sonnet does not fit this workload in one request. Claude 3.5 Sonnet has no published cached-input rate, so cached tokens use its listed input rate.

    Confidence: rate-fallback

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
2
Claude 3.5 Sonnet only
2
Gemini 3.5 Flash only
21
Like-for-like categories
1 / 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.

Math

Like-for-like
Claude 3.5 Sonnet
1.6
Gemini 3.5 Flash
32.9
Weighted basis
2 vs 2 rows
Reading
Gemini 3.5 Flash leads

Agentic

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

Coding

Not comparable
Claude 3.5 Sonnet
49.0
Gemini 3.5 Flash
55.1
Weighted basis
1 vs 1 rows
Reading
Not comparable

Reasoning

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

Knowledge

Not comparable
Claude 3.5 Sonnet
59.4
Gemini 3.5 Flash
40.2
Weighted basis
1 vs 1 rows
Reading
Not comparable

Multilingual

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

Multimodal

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

Instruction following

Not comparable
Claude 3.5 Sonnet
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.

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

    Claude 3.5 Sonnet: 2.069%Gemini 3.5 Flash: 38.966%Normalized gap 36.9Shared source
  • FrontierMath v2 (Tier 4)

    Math

    Claude 3.5 Sonnet: 0.000%Gemini 3.5 Flash: 14.583%Normalized gap 14.6Shared 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

Claude 3.5 Sonnet
$0.0105
Fits in one request
Gemini 3.5 Flash
$0.006
Fits in one request

Gemini 3.5 Flash has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

Claude 3.5 Sonnet
$0.195
Fits in one request
Gemini 3.5 Flash
$0.102
Fits in one request

Gemini 3.5 Flash 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 3.5 Sonnet
$0.81
Does not fit in one request
Cached input priced at the published list-input rate
Gemini 3.5 Flash
$0.15
Fits in one request

Claude 3.5 Sonnet does not fit this workload in one request. Claude 3.5 Sonnet 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.

Context window

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

Claude 3.5 Sonnet

200K

Gemini 3.5 Flash

Cached-input rate

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

Claude 3.5 Sonnet

Not published

Gemini 3.5 Flash

$0.15 per 1M cached input tokens

Google Gemini API pricing

Documented inputs

Claude 3.5 Sonnet

Not sourced

Gemini 3.5 Flash

Not sourced

Documented outputs

Claude 3.5 Sonnet

Not sourced

Gemini 3.5 Flash

Not sourced

Provider availability

Claude 3.5 Sonnet

Not sourced

Gemini 3.5 Flash

Not sourced

Reasoning profile

Claude 3.5 Sonnet

Non-Reasoning

Gemini 3.5 Flash

Reasoning

Weight access

Claude 3.5 Sonnet

Proprietary

Gemini 3.5 Flash

Proprietary

License

Claude 3.5 Sonnet

Proprietary

Gemini 3.5 Flash

Proprietary

Release date

Claude 3.5 Sonnet

2024-06-01

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
Gemini 3.5 Flash has the higher public score estimate, 64.67 versus 48.11, but the 90% score intervals overlap.
Workload cost
Repository review: $0.195 vs $0.102. Cache-heavy agent loop: $0.81 vs $0.15.
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 evidence25 rows

Agentic

  • Terminal-Bench 2.0

    Claude 3.5 Sonnet
    Gemini 3.5 Flash76.2%
    Source

    Not directly comparable

  • MCP Atlas

    Claude 3.5 Sonnet
    Gemini 3.5 Flash83.6%
    Source

    Not directly comparable

  • Toolathlon

    Claude 3.5 Sonnet
    Gemini 3.5 Flash56.5%
    Source

    Not directly comparable

  • OSWorld-Verified

    Claude 3.5 Sonnet
    Gemini 3.5 Flash78.4%
    Source

    Not directly comparable

  • Finance Agent v2

    Claude 3.5 Sonnet
    Gemini 3.5 Flash57.9%
    Source

    Not directly comparable

  • Gert Labs

    Claude 3.5 Sonnet
    Gemini 3.5 Flash61.85%
    Source

    Not directly comparable

  • ResearchClawBench

    Claude 3.5 Sonnet
    Gemini 3.5 Flash18.0%
    Source

    Not directly comparable

Coding

  • SWE-bench Verified

    Claude 3.5 Sonnet49%
    Source
    Gemini 3.5 Flash

    Not directly comparable

  • Terminal-Bench 2.0

    Claude 3.5 Sonnet
    Gemini 3.5 Flash76.2%
    Source

    Not directly comparable

  • SWE-bench Pro

    Claude 3.5 Sonnet
    Gemini 3.5 Flash55.1%
    Source

    Not directly comparable

  • Vibe Code Bench

    Claude 3.5 Sonnet
    Gemini 3.5 Flash48.68%
    Source

    Not directly comparable

  • cursorBench31

    Claude 3.5 Sonnet
    Gemini 3.5 Flash49.8%
    Source

    Not directly comparable

  • cursorBench32

    Claude 3.5 Sonnet
    Gemini 3.5 Flash48.8%
    Source

    Not directly comparable

  • EEBench

    Claude 3.5 Sonnet
    Gemini 3.5 Flash34.3%
    Source

    Not directly comparable

Reasoning

  • MRCRv2

    Claude 3.5 Sonnet
    Gemini 3.5 Flash77.3%
    Source

    Not directly comparable

  • MRCR 1M

    Claude 3.5 Sonnet
    Gemini 3.5 Flash26.6%
    Source

    Not directly comparable

  • ARC-AGI-2

    Claude 3.5 Sonnet
    Gemini 3.5 Flash72.1%
    Source

    Not directly comparable

Knowledge

  • GPQA

    Claude 3.5 Sonnet59.4%
    Source
    Gemini 3.5 Flash

    Not directly comparable

  • GPQA-D

    Claude 3.5 Sonnet
    Gemini 3.5 Flash92.7%
    Source

    Not directly comparable

  • HLE

    Claude 3.5 Sonnet
    Gemini 3.5 Flash40.2%
    Source

    Not directly comparable

Math

  • FrontierMath v2 (Tiers 1-3)

    Shared source
    Claude 3.5 Sonnet2.069%
    Gemini 3.5 Flash38.966%

    Gemini 3.5 Flash leads this result

  • FrontierMath v2 (Tier 4)

    Shared source
    Claude 3.5 Sonnet0.000%
    Gemini 3.5 Flash14.583%

    Gemini 3.5 Flash leads this result

Multimodal

  • CharXiv

    Claude 3.5 Sonnet
    Gemini 3.5 Flash84.2%
    Source

    Not directly comparable

  • MMMU-Pro

    Claude 3.5 Sonnet
    Gemini 3.5 Flash83.6%
    Source

    Not directly comparable

  • Blueprint-Bench 2

    Claude 3.5 Sonnet
    Gemini 3.5 Flash33.6%
    Source

    Not directly comparable

Frequently asked questions

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

Gemini 3.5 Flash has the higher public score estimate, 64.67 versus 48.11, but the 90% score intervals overlap. The higher estimate is not a decisive winner because the uncertainty ranges overlap.

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

For the stated presets, chat costs $0.0105 on Claude 3.5 Sonnet and $0.006 on Gemini 3.5 Flash; repository review costs $0.195 and $0.102; the cache-heavy agent loop costs $0.81 and $0.15. Claude 3.5 Sonnet does not fit this workload in one request. Claude 3.5 Sonnet has no published cached-input rate, so cached tokens use its listed input rate.

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

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

Related comparisons

Last updated August 18, 2026

Watch Claude 3.5 Sonnet vs Gemini 3.5 Flash

One weekly email when material rank, price, or benchmark evidence changes make this matchup worth revisiting.

Read a sample issue

Join 2,000+ readers.