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Data

Claude Sonnet 5 vs Gemini 3.8 Flash

Updated October 17, 2026. Rank says Gemini 3.8 Flash is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.

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Decision reading

Gemini 3.8 Flash has the higher public score estimate, 69.25 versus 64.84, but the 90% score intervals overlap. Treat that as a lead, not a settled winner. 16 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

Model A
Anthropic logo

Anthropic

64.84/100

Supported · Public rank #36

90% interval 59.9–69.8

Model B
Google logo

Google

69.25/100

Supported · Public rank #22

90% interval 63.6–74.9

Shared results
16
Claude Sonnet 5 only
13
Gemini 3.8 Flash only
15
Like-for-like categories
3 / 8
Supported: Claude Sonnet 5 and Gemini 3.8 FlashHow the comparison works

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.

  • Coding work

    Code generation, repair, and software-engineering tasks

    Gemini 3.8 Flash

    Gemini 3.8 Flash has the higher public coding point estimate, 61 to 57.5, with Supported evidence for both models. The conditional ranges do not establish rank confidence.

    Confidence: limited
  • Chat turn cost

    1K fresh input + 500 output tokens

    Gemini 3.8 Flash

    Gemini 3.8 Flash 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

    Gemini 3.8 Flash

    Gemini 3.8 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 3.8 Flash

    Gemini 3.8 Flash has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates
  • Agentic work

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

    No clear pick

    The like-for-like agentic result is a practical tie on the public lane (within 0.5 points).

    Confidence: limited
  • Long documents

    Prompts that approach the documented context limit

    No clear pick

    The documented context windows are equal.

    Confidence: documented

Which one for a specific job

Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.

The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.

57.5Claude Sonnet 561.0Gemini 3.8 Flash

Like-for-like · BenchAlign v5.8

Gemini 3.8 Flash has the higher coding point estimate. Conditional score ranges do not establish rank confidence.

Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.

Same basis rules as the category table below

What is actually comparable

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

1 category rests on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.

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.

Bars run 0–100 on each benchmark’s normalized display scale

Category results, on a stated basis

Each row shows the public-lane category score for both models: the BenchAlign v5.8 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

Like-for-like
Claude Sonnet 5
66.3
Supported · #15/128
Gemini 3.8 Flash
65.9
Supported · #16/128
Basis
BenchAlign v5.8 lane · 8 vs 9 public rows
Reading
Practical tie

Coding

Like-for-like
Claude Sonnet 5
57.5
Supported · #25/150
Gemini 3.8 Flash
61.0
Supported · #17/150
Basis
BenchAlign v5.8 lane · 11 vs 8 public rows
Reading
Gemini 3.8 Flash leads · intervals overlap

Knowledge

Like-for-like
Claude Sonnet 5
65.4
Supported · #34/184
Gemini 3.8 Flash
73.5
Supported · #13/184
Basis
BenchAlign v5.8 lane · 6 vs 6 public rows
Reading
Gemini 3.8 Flash leads · intervals overlap

Multimodal

Directional only
Claude Sonnet 5
82.0
#15/54
Gemini 3.8 Flash
87.3
#9/54
Basis
Provisional lane · 1 vs 0 weighted rows
Reading
Directional only

Reasoning

Not comparable
Claude Sonnet 5
82.2
Unranked · 2 rankable rows
Gemini 3.8 Flash
74.3
#17/28
Basis
Provisional lane · 0 vs 2 weighted rows
Reading
Not comparable

Multilingual

Not comparable
Claude Sonnet 5
Not ranked
Gemini 3.8 Flash
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Instruction following

Not comparable
Claude Sonnet 5
Not ranked
Gemini 3.8 Flash
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Math

Not comparable
Claude Sonnet 5
69.4
Unranked · 2 rankable rows
Gemini 3.8 Flash
69.7
Unranked · 2 rankable rows
Basis
Provisional lane · 2 vs 2 weighted rows
Reading
Not comparable

Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.

Supported evidence per lane · bars run 0–100Methodology

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 5
$0.007
Fits in one request
Gemini 3.8 Flash
$0.00262
Fits in one request

Gemini 3.8 Flash has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

Claude Sonnet 5
$0.13
Fits in one request
Gemini 3.8 Flash
$0.04875
Fits in one request

Gemini 3.8 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 Sonnet 5
$0.18
Fits in one request
Gemini 3.8 Flash
$0.0675
Fits in one request

Gemini 3.8 Flash has the lower modeled cost

Costs use the listed standard API rates.

Cached input falls back to the list input rate only where a cached rate is unpublished

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.

Claude Sonnet 5

$0.2 per 1M cached input tokens

Claude API pricing

Gemini 3.8 Flash

$0.075 per 1M cached input tokens

Google Gemini API pricing

Reasoning profile

Claude Sonnet 5

Reasoning

Gemini 3.8 Flash

Reasoning

Weight access

Claude Sonnet 5

Proprietary

Gemini 3.8 Flash

Proprietary

License

Claude Sonnet 5

Proprietary

Gemini 3.8 Flash

Proprietary

Release date

Claude Sonnet 5

2026-06-30

Gemini 3.8 Flash

2026-09-02

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 3.8 Flash has the higher public score estimate, 69.25 versus 64.84, but the 90% score intervals overlap.
Workload cost
Repository review: $0.13 vs $0.04875. Cache-heavy agent loop: $0.18 vs $0.0675.
Context tradeoff
Both models list 1M.
Run the same representative tasks against both endpoints before changing production traffic.

Questions

Which is better, Claude Sonnet 5 or Gemini 3.8 Flash?

Gemini 3.8 Flash has the higher public score estimate, 69.25 versus 64.84, 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 Sonnet 5 or Gemini 3.8 Flash?

Gemini 3.8 Flash has the higher public coding point estimate, 61 to 57.5, with Supported evidence for both models. The conditional ranges do not establish rank confidence.

Which is better for agentic tasks, Claude Sonnet 5 or Gemini 3.8 Flash?

The like-for-like agentic tasks row is a practical tie on the public lane, 66.3 against 65.9, inside the 0.5-point band BenchLM treats as level.

Which costs less, Claude Sonnet 5 or Gemini 3.8 Flash?

For the stated presets, chat costs $0.007 on Claude Sonnet 5 and $0.00263 on Gemini 3.8 Flash; repository review costs $0.13 and $0.04875; the cache-heavy agent loop costs $0.18 and $0.0675. Costs use the listed standard API rates.

Which has the larger context window, Claude Sonnet 5 or Gemini 3.8 Flash?

Both models list the same context window, 1M.

Benchmark evidence

The full public result ledger is available for audit without forcing a wide desktop table onto a phone.

Browse raw public benchmark evidence44 rows

Agentic

  • Terminal-Bench 3.0

    Claude Sonnet 514.6%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • Terminal-Bench 2.1

    Claude Sonnet 580.4%
    Source
    Gemini 3.8 Flash89.4%
    Source

    Gemini 3.8 Flash leads this result

  • BrowseComp

    Claude Sonnet 584.7%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • HLE w/ tools

    Claude Sonnet 557.4%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • OSWorld-Verified

    Claude Sonnet 581.2%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • Terminal-Bench 2.1 (Vals)

    Claude Sonnet 574.5%
    Source
    Gemini 3.8 Flash81.3%
    Source

    Gemini 3.8 Flash leads this result

  • ApprenticeBench

    Shared source
    Claude Sonnet 516%
    Gemini 3.8 Flash24%

    Gemini 3.8 Flash leads this result

  • MazeBench

    Claude Sonnet 50%
    Source
    Gemini 3.8 Flash4%
    Source

    Gemini 3.8 Flash leads this result

  • Finance Agent v2

    Claude Sonnet 5—
    Gemini 3.8 Flash61.4%
    Source

    Not directly comparable

  • Terminal-Bench 4.0

    Claude Sonnet 5—
    Gemini 3.8 Flash19.10%
    Source

    Not directly comparable

  • OSWorld 2.0

    Claude Sonnet 5—
    Gemini 3.8 Flash59.0%
    Source

    Not directly comparable

  • Hermes Index

    Claude Sonnet 5—
    Gemini 3.8 Flash38.1%
    Source

    Not directly comparable

  • Hermes Bench

    Claude Sonnet 5—
    Gemini 3.8 Flash62.2%
    Source

    Not directly comparable

Coding

  • SWE-bench Verified

    Claude Sonnet 585.2%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • SWE-bench Pro

    Claude Sonnet 563.2%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • SWE Multilingual

    Claude Sonnet 578.3%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • SWE Multimodal

    Claude Sonnet 528.1%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • Terminal-Bench 2.1

    Claude Sonnet 580.4%
    Source
    Gemini 3.8 Flash89.4%
    Source

    Gemini 3.8 Flash leads this result

  • FrontierCode 1.1 Main

    Claude Sonnet 542.7%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • CursorBench 3.2

    Shared source
    Claude Sonnet 561.5%
    Gemini 3.8 Flash69.2%

    Gemini 3.8 Flash leads this result

  • VulcanBench CII v1

    Claude Sonnet 589.2%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • LiveCodeBench (Vals)

    Claude Sonnet 582.4%
    Source
    Gemini 3.8 Flash89.5%
    Source

    Gemini 3.8 Flash leads this result

  • SWE-bench (Vals)

    Claude Sonnet 579.6%
    Source
    Gemini 3.8 Flash80.0%
    Source

    Gemini 3.8 Flash leads this result

  • CursorBench 4.0

    Shared source
    Claude Sonnet 534.1%
    Gemini 3.8 Flash39.6%

    Gemini 3.8 Flash leads this result

  • DeepSWE

    Claude Sonnet 5—
    Gemini 3.8 Flash73.8%
    Source

    Not directly comparable

  • FrontierSWE v2

    Claude Sonnet 5—
    Gemini 3.8 Flash19.6%
    Source

    Not directly comparable

  • Bug Hunt Bench

    Claude Sonnet 5—
    Gemini 3.8 Flash18.0 fixes
    Source

    Not directly comparable

Reasoning

  • ARC-AGI-1

    Claude Sonnet 5—
    Gemini 3.8 Flash98.50%
    Source

    Not directly comparable

  • ARC-AGI-2

    Claude Sonnet 5—
    Gemini 3.8 Flash89.2%
    Source

    Not directly comparable

  • ARC-AGI-3

    Claude Sonnet 5—
    Gemini 3.8 Flash10.4%
    Source

    Not directly comparable

Multimodal

  • CharXiv

    Claude Sonnet 588.3%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • CharXiv w/o tools

    Claude Sonnet 577%
    Source
    Gemini 3.8 Flash86.2%
    Source

    Gemini 3.8 Flash leads this result

  • LVBench

    Claude Sonnet 5—
    Gemini 3.8 Flash87.1%
    Source

    Not directly comparable

Knowledge

  • HLE

    Claude Sonnet 557.4%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • HLE w/o tools

    Claude Sonnet 543.2%
    Source
    Gemini 3.8 Flash—

    Not directly comparable

  • HLE-Verified

    Shared source
    Claude Sonnet 531.0%
    Gemini 3.8 Flash54.9%

    Gemini 3.8 Flash leads this result

  • Claude Sonnet 580.1%
    Gemini 3.8 Flash86.2%

    Gemini 3.8 Flash leads this result

  • GPQA Diamond (Vals)

    Claude Sonnet 588.9%
    Source
    Gemini 3.8 Flash94.4%
    Source

    Gemini 3.8 Flash leads this result

  • MMLU-Pro (Vals)

    Claude Sonnet 587.5%
    Source
    Gemini 3.8 Flash90.2%
    Source

    Gemini 3.8 Flash leads this result

  • BioMysteryBench (human-solvable)

    Claude Sonnet 5—
    Gemini 3.8 Flash88.8%
    Source

    Not directly comparable

  • BioMysteryBench (human-difficult)

    Claude Sonnet 5—
    Gemini 3.8 Flash56.5%
    Source

    Not directly comparable

Instruction following

  • Gray Swan IPI (15 attempts)

    Claude Sonnet 5—
    Gemini 3.8 Flash5.5%
    Source

    Not directly comparable

Math

  • FrontierMath v2 (Tiers 1-3)

    Shared source
    Claude Sonnet 565.614%
    Gemini 3.8 Flash68.421%

    Gemini 3.8 Flash leads this result

  • FrontierMath v2 (Tier 4)

    Shared source
    Claude Sonnet 529.268%
    Gemini 3.8 Flash21.951%

    Claude Sonnet 5 leads this result

44 public results · 16 shared

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Last updated October 17, 2026