Claude Opus 4.5 vs Claude Sonnet 4.5

Benchmark Performance

Available Benchmarks

BenchmarkClaude Opus 4.5Claude Sonnet 4.5
Berkeley Function Calling Leaderboardv4-ede5081a24bc · overall_accuracy · leader33.47100% of row best · percent · Claude-Opus-4-5-20251101 (Prompt)24.9074% of row best · percent · Claude-Sonnet-4-5-20250929 (Prompt)
LMArena Document Arenadocument-2026-07-30-011508720696 · arena_rating · statistical tie1,461.65100% of row best · rating · claude-opus-4-5-20251101; 95% CI [1451.22442739, 1472.08183979]; votes 7965; rank 191,446.1999% of row best · rating · claude-sonnet-4-5-20250929; 95% CI [1439.60004073, 1452.78970477]; votes 28634; rank 22
LMArena Search Arenasearch-2026-08-24-011508720696 · arena_rating · leader1,179.64100% of row best · rating · claude-opus-4-5-search; 95% CI [1174.02872051, 1185.26030035]; votes 61573; rank 191,158.4698% of row best · rating · claude-sonnet-4-5-search; 95% CI [1153.41447529, 1163.49714967]; votes 127378; rank 24
LMArena Text Arenatext-2026-09-01-011508720696 · arena_rating · leader1,447.19100% of row best · rating · claude-opus-4-5-20251101-high-32k; 95% CI [1443.28922560, 1451.09589305]; votes 36271; rank 461,433.9599% of row best · rating · claude-sonnet-4-5-20250929-high-32k; 95% CI [1431.13754052, 1436.75329939]; votes 81031; rank 79
Overall ResultCounted from the protocol-matched rows above · 1 tie3 benchmark winsOverall lead0 benchmark wins

Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.

FieldAt a Glance
Anthropic · activeClaude Opus 4.5Verified Sep 3, 2026
Anthropic · activeClaude Sonnet 4.5Verified Sep 3, 2026
Not a Valid ComparisonThese records do not share a sourced modality and workload.

Technical Differences

Side-by-Side Facts

Interactive only
FieldClaude Opus 4.5Claude Sonnet 4.5
DeveloperAnthropicAnthropic
FamilyClaude 4Claude 4
ModelClaude Opus 4.5Claude Sonnet 4.5
VersionClaude Opus 4.5Claude Sonnet 4.5
Lifecycleactiveactive
Released2025-11-242025-09-29
Knowledge cutoff2025-05-012025-01-01
Input modalitiesUnknownUnknown
Output modalitiesUnknownUnknown
Context window200,000200,000
Total parametersUnknownUnknown
Active parametersUnknownUnknown
LicenseUnknownUnknown
Open weightsNoNo
API availableYesYes
Self-hostableNoNo
Provider accessAnthropic (Standard)Anthropic (Standard)
Capabilitieschat, generation, reasoning, structured_outputs, toolschat, generation, reasoning, structured_outputs, tools

13 comparable fields · 4 material differences · Interactive comparison only; indexing gate not met

Claude Opus 4.5 Capabilities

chatgenerationreasoningstructured outputstools
Input price
Output price
Serving providers1
Canonical IDanthropic/claude-opus-4-5

Claude Sonnet 4.5 Capabilities

chatgenerationreasoningstructured outputstools
Input price
Output price
Serving providers1
Canonical IDanthropic/claude-sonnet-4-5

Primary Evidence

Sources and Freshness

Questions

Claude Opus 4.5 vs Claude Sonnet 4.5 FAQs

Is Claude Opus 4.5 or Claude Sonnet 4.5 better for coding?+

This comparison does not currently contain a protocol-matched coding benchmark for both Claude Opus 4.5 and Claude Sonnet 4.5, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.

Which is cheaper, Claude Opus 4.5 or Claude Sonnet 4.5?+

Neither model has a directly sourced input price in this comparison. Neither model has a directly sourced output price in this comparison.

Which has a larger context window, Claude Opus 4.5 or Claude Sonnet 4.5?+

Neither model has a larger sourced context window in this comparison. Claude Opus 4.5 is 200,000 and Claude Sonnet 4.5 is 200,000.

Which performs better in benchmarks, Claude Opus 4.5 or Claude Sonnet 4.5?+

Claude Opus 4.5 leads the current overall benchmark count. The result uses 4 protocol-matched benchmarks from 2 publishers; it is not a universal quality score.

Can Claude Opus 4.5 or Claude Sonnet 4.5 be self-hosted?+

Both models have the same recorded self-hosting status: unsupported. Claude Opus 4.5 is not marked open weight; Claude Sonnet 4.5 is not marked open weight.

Can Claude Opus 4.5 and Claude Sonnet 4.5 understand images?+

Claude Opus 4.5 is not documented with image input; Claude Sonnet 4.5 is not documented with image input. This reflects supported input modalities, not vision quality.

Which can generate longer answers, Claude Opus 4.5 or Claude Sonnet 4.5?+

Neither has a larger sourced maximum output. Claude Opus 4.5 is 64,000 and Claude Sonnet 4.5 is 64,000.

Do Claude Opus 4.5 and Claude Sonnet 4.5 support reasoning and tool use?+

Claude Opus 4.5: reasoning and tool calling. Claude Sonnet 4.5: reasoning and tool calling. Feature support does not establish relative quality.

Which is available from more inference providers, Claude Opus 4.5 or Claude Sonnet 4.5?+

Claude Opus 4.5 has 1 sourced provider route; Claude Sonnet 4.5 has 1, a tie.

Which offers better value, Claude Opus 4.5 or Claude Sonnet 4.5?+

There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.

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