Compare · ModelsLive · 2 picked · head to head

Claude Sonnet 5 vs gpt-oss-20b

Side by side · benchmarks, pricing, and signals you can act on.

Winner summary

Claude Sonnet 5 wins 6 of 6 shared benchmarks. Leads in knowledge · general · math.

Category leads
knowledge·Claude Sonnet 5general·Claude Sonnet 5math·Claude Sonnet 5coding·Claude Sonnet 5
Hype vs Reality
Claude Sonnet 5
#66 by perf·#10 by attention
DESERVED
gpt-oss-20b
#97 by perf·no signal
QUIET
Best value
104.1x better value than Claude Sonnet 5
Claude Sonnet 5
9.5 pts/$
$6.00/M
gpt-oss-20b
983.3 pts/$
$0.05/M
Vendor risk
Anthropic logo
Anthropic
$965.0B·Tier 1
Medium risk
OpenAI logo
OpenAI
$840.0B·Tier 1
Medium risk
Head to head
Claude Sonnet 5gpt-oss-20b
Chess Puzzles
Claude Sonnet 5 leads by +31.6
Chess Puzzles · tests strategic and tactical reasoning by having models solve chess puzzle positions, evaluating lookahead and pattern recognition abilities.
Claude Sonnet 5
31.6
gpt-oss-20b
0.0
Dtbench
Claude Sonnet 5 leads by +40.8
Claude Sonnet 5
87.5
gpt-oss-20b
46.7
GPQA diamond
Claude Sonnet 5 leads by +39.6
Graduate-Level Google-Proof QA (Diamond set) · expert-crafted questions in physics, biology, and chemistry that are difficult even for domain PhDs.
Claude Sonnet 5
87.4
gpt-oss-20b
47.7
Lmca
Claude Sonnet 5 leads by +41.8
Claude Sonnet 5
58.9
gpt-oss-20b
17.1
OTIS Mock AIME 2024-2025
Claude Sonnet 5 leads by +29.5
OTIS Mock AIME 2024-2025 · simulated American Invitational Mathematics Examination problems testing advanced problem-solving skills.
Claude Sonnet 5
94.7
gpt-oss-20b
65.2
WeirdML
Claude Sonnet 5 leads by +27.9
WeirdML · tests models on unusual and adversarial machine learning tasks that require creative problem-solving beyond standard patterns.
Claude Sonnet 5
68.8
gpt-oss-20b
40.9
Full benchmark table
BenchmarkClaude Sonnet 5gpt-oss-20b
Chess Puzzles
Chess Puzzles · tests strategic and tactical reasoning by having models solve chess puzzle positions, evaluating lookahead and pattern recognition abilities.
31.60.0
Dtbench
87.546.7
GPQA diamond
Graduate-Level Google-Proof QA (Diamond set) · expert-crafted questions in physics, biology, and chemistry that are difficult even for domain PhDs.
87.447.7
Lmca
58.917.1
OTIS Mock AIME 2024-2025
OTIS Mock AIME 2024-2025 · simulated American Invitational Mathematics Examination problems testing advanced problem-solving skills.
94.765.2
WeirdML
WeirdML · tests models on unusual and adversarial machine learning tasks that require creative problem-solving beyond standard patterns.
68.840.9
Pricing · per 1M tokens · projected $/mo at 10M tokens
ModelInputOutputContextProjected $/mo
Anthropic logoClaude Sonnet 5$2.00$10.001.0M tokens (~500 books)$40.00
OpenAI logogpt-oss-20b$0.02$0.09131K tokens (~66 books)$0.36