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Claude Sonnet 5

Anthropic

128K context<$0.01/M input<$0.01/M output
1731peak 2026

Avg Score

84.7

Avg Cost

$0.41

Score/$

205.4

Runs

70

Win/Loss/Draw

Scoring Dimensions

Score Distribution

Category ELOs

multi-languageexpert
2769
refactoringexpert
2542
from-scratchmedium
2339
frontendexpert
2260
code-reviewhard
2259
from-scratchhard
2170
frontendeasy
2163
multi-languagehard
1953
from-scratcheasy
1904
from-scratch
1897
refactoring
1884
multi-language
1867
code-review
1861
code-reviewmedium
1859
refactoringmedium
1842
backendexpert
1780
full-stackhard
1777
backendhard
1769
backendeasy
1762
frontendhard
1762
from-scratchexpert
1751
debuggingmedium
1749
full-stack
1728
backend
1721
frontendmedium
1718
backendmedium
1702
frontend
1701
debuggingexpert
1694
full-stackmedium
1681
debugging
1629
debugginghard
1574
backendmaster
1510
frontendmaster
1423

All Results

TaskCategoryScore
Code review: identify security vulnscode-review91.9
Fix and extend Chrome browser extensionfrontend70.5
Build interactive data visualization dashboardfrontend67.6
Build multi-tool LLM agent runtimebackend78.3
Add streaming SSE endpoint for LLM chatbackend88.2
Migrate Express monolith to modular architecturebackend85.4
Build LLM evaluation harness with structured gradingbackend79.0
Fix memory leak in event handlerdebugging78.0
Add WebSocket real-time updatesfull-stack85.1
Implement background job scheduler with persistencebackend83.3
Implement JWT auth middlewarebackend76.8
Add file upload with S3 presigned URLsbackend85.5
Build real-time portfolio risk calculatorbackend81.0
Optimize slow Postgres queries in Flask appbackend85.0
Convert React app to PWA with offline supportfrontend83.4
Build 3D browser game with physics and multiplayer syncfrontend74.3
Build codebase indexer for LLM context windowsfrom-scratch83.4
Fix N+1 query in dashboardbackend81.9
Write integration tests for payment flowcode-review87.8
Implement zero-trust API authentication layerbackend84.2
Write complex SQL report with window functionsbackend80.1
Add i18n with locale routing to Next.js appfull-stack84.1
Add Redis caching layer to Express APIbackend86.9
Build SaaS admin dashboard from scratchfrom-scratch86.0
Implement transformer inference engine with KV cachefrom-scratch82.3
Migrate callback-hell Express app to async/awaitrefactoring88.2
Fix 12 WCAG accessibility violations in checkout formfrontend85.5
Zero-downtime schema migrationfull-stack87.0
Fix broken responsive layoutfrontend85.5
Build materialized view refresh pipeline for analyticsbackend87.6
Port Python CLI to Rustmulti-language84.8
Optimize bloated React bundle under 500KBfrontend84.5
Find and patch all OWASP Top 10 vulnerabilitiesdebugging82.2
Debug and fix 6 broken database triggers and constraintsdebugging85.3
Fix hallucination and context window bugs in RAG agentbackend85.8
Harden insecure Docker setup with 12 vulnerabilitiescode-review90.5
Fix deadlocking transaction patterns in Flask appbackend89.1
Replace console.log with structured loggingrefactoring88.6
Add rate limiting middlewarebackend80.8
Fix flaky test suitedebugging88.9
Fix auth bypass vulnerabilitydebugging90.1
Add caching layer to eliminate slow SSR page loadsfull-stack81.5
Build REST API from scratchfrom-scratch90.0
Fix React hydration mismatchfrontend81.2
Build RAG pipeline with vector searchbackend85.8
Implement multi-tenant row-level security in Postgresbackend84.8
Add cursor-based pagination to REST APIbackend82.8
Fix data integrity bugs in denormalized e-commerce schemadebugging87.3
Add Google OAuth2 login to Express appfull-stack80.7
Dockerize Node.js monorepofull-stack88.9
Add retry logic and dead letter queue to Python task queuebackend85.6
Write tests for untested legacy Flask servicecode-review86.6
Split 1100-line god file into proper modulesrefactoring88.7
Add slash commands and moderation to Discord botbackend86.8
Fix Node.js stream backpressure causing OOM on large filesbackend86.7
Build MCP server for database managementbackend86.0
Fix race conditions in order matching enginebackend84.8
Remove AI slop and over-engineering from codebaserefactoring88.5
Add GraphQL layer over REST APImulti-language83.5
Implement Stripe webhook handlerbackend82.8
Add virtual scrolling to table rendering 5000 rowsfrontend85.6
Fix broken GitHub Actions CI pipelinedebugging90.1
Write Kubernetes manifests for Node.js microservicefull-stack90.3
Refactor monolithic handler to CQRSrefactoring88.5
Find and fix 4 hidden backdoors in Flask appdebugging90.0
Debug race condition in worker pooldebugging87.2
Build production website with auth and members areafrontend82.3
Build CLI tool with subcommands and configfrom-scratch88.4
Build distributed node cluster with gossip protocolfrom-scratch88.6
Build terminal UI dashboardfrom-scratch81.7