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Head-to-head comparison

Claude Sonnet 5 vs. Gemini 3.8 Flash

Compare published benchmark results from matching versions and cohorts, API pricing, and technical specifications. Any documented test setup differences remain visible.

shared result series
23
distinct benchmarks
23
latest retrieval
2026-09-02

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Specifications

General specifications

Release date, availability, context window, architecture, and published parameter counts at a glance. Undisclosed details remain marked as unavailable.

Specifications for Claude Sonnet 5 and Gemini 3.8 Flash
AttributeClaude Sonnet 5Gemini 3.8 Flash
ProviderAnthropicGoogle
ReleasedJun 30, 2026Sep 2, 2026
AvailabilityActiveActive
Model typeProprietaryProprietary
ParametersNot publishedNot published
ArchitectureNot publishedNot published
Context window1,000,000 tokens1,048,576 tokens
Knowledge cutoffJanuary 2026March 2026
Technical sourcesModel, ContextModel, Knowledge cutoff

Pricing

API pricing compared

The table compares official standard API rates per 1M tokens, including published cache pricing. Batch, fast, priority, regional surcharges, tool calls, and cloud platform pricing are excluded.

API pricing for Claude Sonnet 5 and Gemini 3.8 Flash
Price typeClaude Sonnet 5Gemini 3.8 Flash
API input$2$0.75
API output$10$3.75
Cache read$0.2$0.07
Cache write (5 min.)$2.5Not listed
Cache write (1 hr.)$4Not listed
Price verified09/02/2026 Source09/02/2026 Source
Claude Sonnet 5Gemini 3.8 Flash
API inputUSD per 1M tokens, base tier
Claude Sonnet 5$2
Gemini 3.8 FlashLower price$0.75
API outputUSD per 1M tokens, base tier
Claude Sonnet 5$10
Gemini 3.8 FlashLower price$3.75
Cache readUSD per 1M tokens, base tier
Claude Sonnet 5$0.2
Gemini 3.8 FlashLower price$0.075

Key to the marks:better valuebetter, but not conclusivetie

Pricing by provider

Direct developer pricing and provider endpoint tariffs routed through OpenRouter are listed separately. Prices are in USD per 1M tokens. Context-dependent direct tiers plus regional, Flex, Priority, and other OpenRouter tariffs remain individually identifiable.

Provider pricing for Claude Sonnet 5 and Gemini 3.8 Flash
ModelProviderPurchase route and tariffInput per 1M tokensOutput per 1M tokensSource
Claude Sonnet 5AnthropicDirect from developerStandard APILowest listed price: $2Lowest listed price: $10Source09/02/2026
Amazon BedrockVia OpenRouteramazon-bedrock/globalLowest listed price: $2Lowest listed price: $10Source09/02/2026
Amazon BedrockVia OpenRouteramazon-bedrock/us-east-1$2.2$11Source09/02/2026
AnthropicVia OpenRouteranthropicLowest listed price: $2Lowest listed price: $10Source09/02/2026
AzureVia OpenRouterazure/globalLowest listed price: $2Lowest listed price: $10Source09/02/2026
AzureVia OpenRouterazure/usLowest listed price: $2Lowest listed price: $10Source09/02/2026
Claude Platform on AWSVia OpenRouterclaude-on-awsLowest listed price: $2Lowest listed price: $10Source09/02/2026
GoogleVia OpenRoutergoogle-vertex/europe$2.2$11Source09/02/2026
GoogleVia OpenRoutergoogle-vertex/globalLowest listed price: $2Lowest listed price: $10Source09/02/2026
GoogleVia OpenRoutergoogle-vertex/us$2.2$11Source09/02/2026
Gemini 3.8 FlashGoogleDirect from developerStandard API$0.75$3.75Source09/02/2026
GoogleVia OpenRoutergoogle-vertex/global$0.75$3.75Source09/02/2026
GoogleVia OpenRoutergoogle-vertex/global/flexLowest listed price: $0.375Lowest listed price: $1.875Source09/02/2026
GoogleVia OpenRoutergoogle-vertex/global/priority$1.35$6.75Source09/02/2026
Google AI StudioVia OpenRoutergoogle-ai-studio$0.75$3.75Source09/02/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/flexLowest listed price: $0.375Lowest listed price: $1.875Source09/02/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/priority$1.35$6.75Source09/02/2026

Performance

Shared benchmarks

Only published results with the same benchmark version, task, metric, and comparison cohort are paired. Different reasoning levels, agents, harnesses, or output limits appear directly in the table.

Capability profile from matched benchmarks

Each axis averages directly matched benchmark families. A value of 100 means the stronger value within this pair, not a universal quality score.

255075100CodingReasoningMathematicsKnowledgeFinanceLegalAgentic tasksMultimodal
Claude Sonnet 5
Gemini 3.8 Flash
Coding: 78.3 / 95.8 (5 benchmark families)
Reasoning: 94.1 / 100 (1 benchmark family)
Mathematics: 100 / 62.3 (1 benchmark family)
Knowledge: 97 / 100 (1 benchmark family)
Finance: 94.9 / 97.9 (4 benchmark families)
Legal: 82.2 / 97.7 (3 benchmark families)
Agentic tasks: 85.9 / 100 (2 benchmark families)
Multimodal: 93.2 / 100 (1 benchmark family)

23 matched rows from 23 benchmark families were considered. The radar shows 8 of 12 comparable categories.

Claude Sonnet 5Gemini 3.8 Flash
Code MigrationOverall. Higher is better. No documented setup difference
Claude Sonnet 5Winner44.392 %
Gemini 3.8 Flash36.546 %
EMBOverall. Higher is better. No documented setup difference
Claude Sonnet 566.316 %
Gemini 3.8 FlashWinner72.196 %
Finance Agent (v2)Overall. Higher is better. No documented setup difference
Claude Sonnet 553.909 %
Gemini 3.8 FlashWinner61.435 %
GPQA DiamondOverall. Higher is better. No documented setup difference
Claude Sonnet 588.889 %
Gemini 3.8 FlashWinner94.444 %
Harvey's Legal Agent BenchmarkOverall · Task fully resolved. Higher is better. No documented setup difference
Claude Sonnet 55 %
Gemini 3.8 FlashWinner10 %
Legal Research BenchOverall · All-pass. Higher is better. No documented setup difference
Claude Sonnet 5Winner41.827 %
Gemini 3.8 Flash38.942 %
LegalBenchOverall. Higher is better. No documented setup difference
Claude Sonnet 583.922 %
Gemini 3.8 FlashWinner86.993 %
LiveCodeBench v6Overall. Higher is better. No documented setup difference
Claude Sonnet 582.429 %
Gemini 3.8 FlashWinner89.484 %
MedCodeOverall. Higher is better. No documented setup difference
Claude Sonnet 547.54 %
Gemini 3.8 FlashWinner48.135 %
MedScribeOverall. Higher is better. No documented setup difference
Claude Sonnet 576.054 %
Gemini 3.8 FlashWinner84.496 %
MMLU-ProOverall. Higher is better. No documented setup difference
Claude Sonnet 587.545 %
Gemini 3.8 FlashWinner90.221 %
MMMU-ProOverall. Higher is better. No documented setup difference
Claude Sonnet 583.006 %
Gemini 3.8 FlashWinner89.075 %

Key to the marks:better valuebetter, but not conclusivetie

Benchmark scores for Claude Sonnet 5 and Gemini 3.8 Flash
Benchmark and taskClaude Sonnet 5Gemini 3.8 FlashSource
Code MigrationOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner44.392 %
36.546 %
Vals AI
Source details
Data as of: 09/01/2026
EMBOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
66.316 %
Winner72.196 %
Vals AI
Source details
Data as of: 09/01/2026
Finance Agent (v2)Overall
Test details
No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better
53.909 %
Winner61.435 %
Vals AI
Source details
Data as of: 09/01/2026
GPQA DiamondOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
88.889 %
Winner94.444 %
Vals AI
Source details
Data as of: 09/01/2026
Harvey's Legal Agent BenchmarkOverall · Task fully resolved
Test details
No documented difference in the test setupVersion: 1Metric: task resolution rateScoring: Higher is better
5 %
Winner10 %
Vals AI
Source details
Data as of: 09/01/2026
Legal Research BenchOverall · All-pass
Test details
No documented difference in the test setupVersion: 1Metric: all-pass rateScoring: Higher is better
Winner41.827 %
38.942 %
Vals AI
Source details
Data as of: 09/01/2026
LegalBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
83.922 %
Winner86.993 %
Vals AI
Source details
Data as of: 09/01/2026
LiveCodeBench v6Overall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
82.429 %
Winner89.484 %
Vals AI
Source details
Data as of: 09/01/2026
MedCodeOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
47.54 %
Winner48.135 %
Vals AI
Source details
Data as of: 09/01/2026
MedScribeOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
76.054 %
Winner84.496 %
Vals AI
Source details
Data as of: 09/01/2026
MMLU-ProOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
87.545 %
Winner90.221 %
Vals AI
Source details
Data as of: 09/01/2026
MMMU-ProOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
83.006 %
Winner89.075 %
Vals AI
Source details
Data as of: 09/01/2026
MortgageTaxOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner70.032 %
65.342 %
Vals AI
Source details
Data as of: 09/01/2026
ProgramBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
0 %
Winner1 %
Vals AI
Source details
Data as of: 09/01/2026
ProofBenchOverall
Test details
No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is better
Winner77 %
48 %
Vals AI
Source details
Data as of: 09/01/2026
Public Benefits Bench v1.1Overall
Test details
No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is better
Winner66.035 %
65.291 %
Vals AI
Source details
Data as of: 09/01/2026
SAGEOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner48.925 %
35.064 %
Vals AI
Source details
Data as of: 09/01/2026
SkillsBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands
46.476 %
Winner57.985 %
Vals AI
Source details
Data as of: 09/01/2026
SWE-bench VerifiedOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
79.6 %
Winner80 %
Vals AI
Source details
Data as of: 09/01/2026
TaxEval v2Overall
Test details
No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better
Winner75.634 %
74.448 %
Vals AI
Source details
Data as of: 09/01/2026
Terminal-Bench 2.1Overall
Test details
No documented difference in the test setupVersion: 2.1Metric: accuracyScoring: Higher is better
74.532 %
Winner81.273 %
Vals AI
Source details
Data as of: 09/01/2026
Vals IndexOverall
Test details
No documented difference in the test setupVersion: 2Metric: weighted index scoreScoring: Higher is better
59.61 %
Winner62.252 %
Vals AI
Source details
Data as of: 09/01/2026
Vibe Code Bench v1.1Overall
Test details
No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands
Winner81.325 %
78.651 %
Vals AI
Source details
Data as of: 09/01/2026

Key to the marks:better valuebetter, but not conclusivetie

How to read this comparison

Winning one benchmark is not an overall verdict

Your workload, budget, and required context length matter most. A coding benchmark says little about visual understanding or agent performance.

The standard price table uses direct developer rates. The provider comparison labels OpenRouter endpoints, regions, and special tariffs separately.

Every result links to its measurement source and retrieval date. Labels distinguish vendor reports, official benchmark leaderboards, and independent evaluations. Disputed or archived results are excluded.

More matchups

Related LLM comparisons

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View the complete LLM comparison