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Head-to-head comparison

Claude Opus 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
25
distinct benchmarks
25
latest retrieval
2026-09-04

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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 Opus 5 and Gemini 3.8 Flash
AttributeClaude Opus 5Gemini 3.8 Flash
ProviderAnthropicGoogle
ReleasedJul 24, 2026Sep 2, 2026
AvailabilityActiveActive
Model typeProprietaryProprietary
ParametersNot publishedNot published
ArchitectureNot publishedNot published
Context window1,000,000 tokens1,048,576 tokens
Knowledge cutoffMay 2026March 2026
Technical sourcesModel, Knowledge cutoffModel, 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 Opus 5 and Gemini 3.8 Flash
Price typeClaude Opus 5Gemini 3.8 Flash
API input$5$0.75
API output$25$3.75
Cache read$0.5$0.07
Cache write (5 min.)$6.25Not listed
Cache write (1 hr.)$10Not listed
Price verified07/30/2026 Source09/02/2026 Source
Claude Opus 5Gemini 3.8 Flash
API inputUSD per 1M tokens, base tier
Claude Opus 5$5
Gemini 3.8 FlashLower price$0.75
API outputUSD per 1M tokens, base tier
Claude Opus 5$25
Gemini 3.8 FlashLower price$3.75
Cache readUSD per 1M tokens, base tier
Claude Opus 5$0.5
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 Opus 5 and Gemini 3.8 Flash
ModelProviderPurchase route and tariffInput per 1M tokensOutput per 1M tokensSource
Claude Opus 5AnthropicDirect from developerStandard APILowest listed price: $5Lowest listed price: $25Source07/30/2026
Amazon BedrockVia OpenRouteramazon-bedrockLowest listed price: $5Lowest listed price: $25Source09/12/2026
Amazon BedrockVia OpenRouteramazon-bedrock/eu-west-1$5.5$27.5Source09/12/2026
Amazon BedrockVia OpenRouteramazon-bedrock/us-east-1$5.5$27.5Source09/12/2026
AnthropicVia OpenRouteranthropicLowest listed price: $5Lowest listed price: $25Source09/12/2026
AnthropicVia OpenRouteranthropic/fast$10$50Source09/12/2026
AzureVia OpenRouterazure/globalLowest listed price: $5Lowest listed price: $25Source09/12/2026
AzureVia OpenRouterazure/usLowest listed price: $5Lowest listed price: $25Source09/12/2026
Claude Platform on AWSVia OpenRouterclaude-on-awsLowest listed price: $5Lowest listed price: $25Source09/12/2026
GoogleVia OpenRoutergoogle-vertex/europe$5.5$27.5Source09/12/2026
GoogleVia OpenRoutergoogle-vertex/globalLowest listed price: $5Lowest listed price: $25Source09/12/2026
GoogleVia OpenRoutergoogle-vertex/us$5.5$27.5Source09/12/2026
Gemini 3.8 FlashGoogleDirect from developerStandard API$0.75$3.75Source09/02/2026
GoogleVia OpenRoutergoogle-vertex/global$0.75$3.75Source09/12/2026
GoogleVia OpenRoutergoogle-vertex/global/flexLowest listed price: $0.375Lowest listed price: $1.875Source09/12/2026
GoogleVia OpenRoutergoogle-vertex/global/priority$1.35$6.75Source09/12/2026
Google AI StudioVia OpenRoutergoogle-ai-studio$0.75$3.75Source09/12/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/flexLowest listed price: $0.375Lowest listed price: $1.875Source09/12/2026
Google AI StudioVia OpenRoutergoogle-ai-studio/priority$1.35$6.75Source09/12/2026

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 Opus 5
Gemini 3.8 Flash
Coding: 99.9 / 73.7 (5 benchmark families)
Reasoning: 98.9 / 100 (1 benchmark family)
Mathematics: 100 / 48.5 (1 benchmark family)
Knowledge: 100 / 98.5 (1 benchmark family)
Finance: 98.9 / 97 (4 benchmark families)
Legal: 88.9 / 90.1 (3 benchmark families)
Agentic tasks: 100 / 96 (2 benchmark families)
Multimodal: 100 / 99.1 (1 benchmark family)

25 matched rows from 25 benchmark families were considered. The radar shows 8 of 13 comparable categories.

Claude Opus 5Gemini 3.8 Flash
BioMysteryBenchOverall. Higher is better. No documented setup difference
Claude Opus 5Winner79.259 %
Gemini 3.8 Flash62.222 %
Code MigrationOverall. Higher is better. No documented setup difference
Claude Opus 5Winner57.473 %
Gemini 3.8 Flash36.546 %
CyberBenchOverall. Higher is better. No documented setup difference
Claude Opus 540.678 %
Gemini 3.8 FlashWinner43.75 %
EMBOverall. Higher is better. No documented setup difference
Claude Opus 5Winner73.556 %
Gemini 3.8 Flash72.196 %
Finance Agent (v2)Overall. Higher is better. No documented setup difference
Claude Opus 558.633 %
Gemini 3.8 FlashWinner61.435 %
GPQA DiamondOverall. Higher is better. No documented setup difference
Claude Opus 593.434 %
Gemini 3.8 FlashWinner94.444 %
Harvey's Legal Agent BenchmarkOverall · Task fully resolved. Higher is better. No documented setup difference
Claude Opus 56.667 %
Gemini 3.8 FlashWinner10 %
Legal Research BenchOverall · All-pass. Higher is better. No documented setup difference
Claude Opus 5Winner55.288 %
Gemini 3.8 Flash38.942 %
LegalBenchOverall. Higher is better. No documented setup difference
Claude Opus 586.974 %
Gemini 3.8 FlashWinner86.993 %
LiveCodeBench v6Overall. Higher is better. No documented setup difference
Claude Opus 589.033 %
Gemini 3.8 FlashWinner89.484 %
MedCodeOverall. Higher is better. No documented setup difference
Claude Opus 5Winner63.57 %
Gemini 3.8 Flash48.135 %
MedScribeOverall. Higher is better. No documented setup difference
Claude Opus 5Winner90.985 %
Gemini 3.8 Flash84.496 %

Key to the marks:better valuebetter, but not conclusivetie

Benchmark scores for Claude Opus 5 and Gemini 3.8 Flash
Benchmark and taskClaude Opus 5Gemini 3.8 FlashSource
BioMysteryBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is betterSettings: Harness: Terminus 2
Winner79.259 %
62.222 %
Vals AI
Source details
Data as of: 09/02/2026
Code MigrationOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner57.473 %
36.546 %
Vals AI
Source details
Data as of: 09/03/2026
CyberBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
40.678 %
Winner43.75 %
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
Winner73.556 %
72.196 %
Vals AI
Source details
Data as of: 09/03/2026
Finance Agent (v2)Overall
Test details
No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better
58.633 %
Winner61.435 %
Vals AI
Source details
Data as of: 09/03/2026
GPQA DiamondOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
93.434 %
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
6.667 %
Winner10 %
Vals AI
Source details
Data as of: 09/03/2026
Legal Research BenchOverall · All-pass
Test details
No documented difference in the test setupVersion: 1Metric: all-pass rateScoring: Higher is better
Winner55.288 %
38.942 %
Vals AI
Source details
Data as of: 09/03/2026
LegalBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
86.974 %
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
89.033 %
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
Winner63.57 %
48.135 %
Vals AI
Source details
Data as of: 09/03/2026
MedScribeOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner90.985 %
84.496 %
Vals AI
Source details
Data as of: 09/03/2026
MMLU-ProOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better
Winner91.591 %
90.221 %
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
Winner89.884 %
89.075 %
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
Winner72.059 %
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
Winner3 %
1 %
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
Winner99 %
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
Winner76.928 %
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
Winner49.426 %
35.064 %
Vals AI
Source details
Data as of: 09/03/2026
SkillsBenchOverall
Test details
No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands
Winner60.441 %
57.985 %
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
Winner97 %
80 %
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
Winner75.143 %
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
Winner84.644 %
81.273 %
Vals AI
Source details
Data as of: 09/03/2026
Vals IndexOverall
Test details
No documented difference in the test setupVersion: 2Metric: weighted index scoreScoring: Higher is better
Winner67.213 %
62.252 %
Vals AI
Source details
Data as of: 09/03/2026
Vibe Code Bench v1.1Overall
Test details
No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands
Winner88.404 %
78.651 %
Vals AI
Source details
Data as of: 09/03/2026

Key to the marks:better valuebetter, but not conclusivetie

Our model tests

Community tests you can inspect

Compare how the models respond to the same prompt. Each test shows the first attempt, with no subsequent fixes to the generated code. These results do not contribute to an overall score.

Pelican on a bicycle

A community classic for free-form SVG drawing.

Claude Opus 5

The API response was not fully received. The model was not evaluated.

First attempt
Run date
7 Sept 2026
API provider
openrouter
Requested API model
anthropic/claude-opus-5
Pinned endpoint
Anthropic | anthropic/claude-opus-5-20260723
Reasoning setting
high
Temperature
Provider default
Token limit including reasoning
8,192 tokens
Test protocol
community-visual-tests-v1
Technical checks
Failed

Not yet visually reviewed. A successful recording does not confirm correct physics or full compliance with the prompt.

Gemini 3.8 Flash

API access was unavailable for this run. The model was not evaluated.

First attempt
Run date
7 Sept 2026
API provider
openrouter
Requested API model
google/gemini-3.8-flash
Pinned endpoint
Google AI Studio | google/gemini-3.8-flash-20260902
Reasoning setting
high
Temperature
Provider default
Token limit including reasoning
8,192 tokens
Test protocol
community-visual-tests-v1
Technical checks
Not run

Not yet visually reviewed. A successful recording does not confirm correct physics or full compliance with the prompt.

Prompt and test conditions

Generate an SVG of a pelican riding a bicycle

Token limit including reasoning: 8,192 tokens

Task origin (Simon Willison)

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

Compare Claude Opus 5 and Gemini 3.8 Flash with other leading models using the same data and benchmark logic.

View the complete LLM comparison