Agentic
Directional only- Claude Opus 4.8
- 80.3
- Claude Sonnet 4.6
- 65.2
- Weighted basis
- 3 vs 2 rows
- Reading
- Directional only
Claude Opus 4.8 vs Claude Sonnet 4.6
Updated August 26, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.
Decision reading
Claude Opus 4.8 has the higher public score estimate, 76.45 versus 64.62, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.
12 results are shared. Category rows based on different benchmark sets are marked directional and do not name a winner.
Which one for your work
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
Long documents
Prompts that approach the documented context limit
Claude Opus 4.8
Claude Opus 4.8 has the larger documented context window.
Confidence: documented
Chat turn cost
1K fresh input + 500 output tokens
Claude Sonnet 4.6
Claude Sonnet 4.6 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Show secondary and unsupported calls
Repository review cost
50K fresh input + 3K output tokens
Claude Sonnet 4.6
Claude Sonnet 4.6 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Coding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
The category averages use different weighted benchmark sets, so they are directional rather than like-for-like.
Confidence: limited
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
The category averages use different weighted benchmark sets, so they are directional rather than like-for-like.
Confidence: limited
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Not enough matched evidence
The page does not recommend a cost winner because at least one model cannot fit the stated workload in one request. Claude Sonnet 4.6 does not fit this workload in one request. Claude Opus 4.8 has no published cached-input rate, so cached tokens use its listed input rate. Claude Sonnet 4.6 has no published cached-input rate, so cached tokens use its listed input rate.
Confidence: rate-fallback
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
21 Claude Opus 4.8 only
12 Shared
8 Claude Sonnet 4.6 only
- Shared results
- 12
- Claude Opus 4.8 only
- 21
- Claude Sonnet 4.6 only
- 8
- Like-for-like categories
- 0 / 8
5 categories use different evidence sets. Those rows remain visible for coverage context but do not name a winner.
Category results, on a stated basis
Each row states whether both averages use the same weighted benchmark set. Directional and not-comparable rows remain visible, but they never receive a winner in this template.
Coding
Directional only- Claude Opus 4.8
- 81.1
- Claude Sonnet 4.6
- 69.1
- Weighted basis
- 2 vs 2 rows
- Reading
- Directional only
Knowledge
Directional only- Claude Opus 4.8
- 62.7
- Claude Sonnet 4.6
- 66.0
- Weighted basis
- 2 vs 4 rows
- Reading
- Directional only
Math
Directional only- Claude Opus 4.8
- 53.9
- Claude Sonnet 4.6
- 26.4
- Weighted basis
- 3 vs 2 rows
- Reading
- Directional only
Multimodal
Directional only- Claude Opus 4.8
- 77.0
- Claude Sonnet 4.6
- 77.4
- Weighted basis
- 2 vs 1 rows
- Reading
- Directional only
Reasoning
Not comparable- Claude Opus 4.8
- 72.1
- Claude Sonnet 4.6
- Not measured
- Weighted basis
- 1 vs 0 rows
- Reading
- Not comparable
Multilingual
Not comparable- Claude Opus 4.8
- Not measured
- Claude Sonnet 4.6
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
Instruction following
Not comparable- Claude Opus 4.8
- Not measured
- Claude Sonnet 4.6
- Not measured
- Weighted basis
- 0 vs 0 rows
- Reading
- Not comparable
| Category | Claude Opus 4.8 | Claude Sonnet 4.6 | Weighted basis | Reading |
|---|---|---|---|---|
| Agentic | 80.3 | 65.2 | Directional only3 vs 2 rows | Directional only |
| Coding | 81.1 | 69.1 | Directional only2 vs 2 rows | Directional only |
| Knowledge | 62.7 | 66.0 | Directional only2 vs 4 rows | Directional only |
| Math | 53.9 | 26.4 | Directional only3 vs 2 rows | Directional only |
| Multimodal | 77.0 | 77.4 | Directional only2 vs 1 rows | Directional only |
| Reasoning | 72.1 | Not measured | Not comparable1 vs 0 rows | Not comparable |
| Multilingual | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
| Instruction following | Not measured | Not measured | Not comparable0 vs 0 rows | Not comparable |
Shape of the matched evidence
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
FrontierMath v2 (Tier 4)
Math
Terminal-Bench 2.0
Agentic
Claude Opus 4.8: 74.6%Claude Sonnet 4.6: 59.1%Normalized gap 15.5Claude Opus 4.8 source Claude Sonnet 4.6 sourceFrontierMath v2 (Tiers 1-3)
Math
CharXiv
Multimodal
Claude Opus 4.8: 89.9%Claude Sonnet 4.6: 77.4%Normalized gap 12.5Claude Opus 4.8 source Claude Sonnet 4.6 sourceOSWorld-Verified
Agentic
Claude Opus 4.8: 83.4%Claude Sonnet 4.6: 72.1%Normalized gap 11.3Claude Opus 4.8 source Claude Sonnet 4.6 source
What each workload costs
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
Chat turn
1K fresh input + 500 output tokens
- Claude Opus 4.8
- $0.0175
- Fits in one request
- Claude Sonnet 4.6
- $0.0105
- Fits in one request
Claude Sonnet 4.6 has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Claude Opus 4.8
- $0.325
- Fits in one request
- Claude Sonnet 4.6
- $0.195
- Fits in one request
Claude Sonnet 4.6 has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Claude Opus 4.8
- $1.35
- Fits in one request
- Cached input priced at the published list-input rate
- Claude Sonnet 4.6
- $0.81
- Does not fit in one request
- Cached input priced at the published list-input rate
Claude Sonnet 4.6 does not fit this workload in one request. Claude Opus 4.8 has no published cached-input rate, so cached tokens use its listed input rate. Claude Sonnet 4.6 has no published cached-input rate, so cached tokens use its listed input rate.
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationClaude Opus 4.8Claude Sonnet 4.6
Context window
Maximum documented context; output-token limits may be lower.
Claude Opus 4.8
Claude Sonnet 4.6
200K
API model ID
Claude Opus 4.8
claude-opus-4-8
Anthropic model overviewClaude Sonnet 4.6
Not sourced
Cached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Claude Opus 4.8
Not published
Claude Sonnet 4.6
Not published
Documented inputs
Claude Opus 4.8
text, image
Anthropic model overviewClaude Sonnet 4.6
Not sourced
Documented outputs
Claude Opus 4.8
Claude Sonnet 4.6
Not sourced
Provider availability
Claude Opus 4.8
Generally Available · Claude API
Anthropic model overviewClaude Sonnet 4.6
Not sourced
Reasoning profile
Claude Opus 4.8
Reasoning
Claude Sonnet 4.6
Non-Reasoning
Weight access
Claude Opus 4.8
Proprietary
Claude Sonnet 4.6
Proprietary
License
Claude Opus 4.8
Proprietary
Claude Sonnet 4.6
Proprietary
Release date
Claude Opus 4.8
2026-05-28
Claude Sonnet 4.6
2026-02-01
If you already use one of these models
- Deployment change
- Both entries list Anthropic as the provider. Confirm endpoint, model ID, limits, and feature support before switching.
- Quality signal
- Claude Opus 4.8 has the higher public score estimate, 76.45 versus 64.62, but the 90% score intervals overlap.
- Workload cost
- Repository review: $0.325 vs $0.195. Cache-heavy agent loop: $1.35 vs $0.81.
- Context tradeoff
- Claude Opus 4.8 has the larger documented window (1M).
Run the same representative tasks against both endpoints before changing production traffic.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence41 rows
Agentic
Terminal-Bench 3.0
Claude Opus 4.821.1%SourceClaude Sonnet 4.6—Not directly comparable
Terminal-Bench 2.0
Claude Opus 4.874.6%SourceClaude Sonnet 4.659.1%SourceClaude Opus 4.8 leads this result
BrowseComp
Claude Opus 4.884.3%SourceClaude Sonnet 4.6—Not directly comparable
DeepSearchQA
Claude Opus 4.893.1%SourceClaude Sonnet 4.6—Not directly comparable
OSWorld-Verified
Claude Opus 4.883.4%SourceClaude Sonnet 4.672.1%SourceClaude Opus 4.8 leads this result
Finance Agent v2
Claude Opus 4.853.9%SourceClaude Sonnet 4.6—Not directly comparable
MCP Atlas
Claude Opus 4.882.2%SourceClaude Sonnet 4.6—Not directly comparable
Toolathlon
Claude Opus 4.859.9%SourceClaude Sonnet 4.6—Not directly comparable
Gert Labs
Shared sourceClaude Opus 4.872.97%Claude Sonnet 4.662.92%Claude Opus 4.8 leads this result
ResearchClawBench
Claude Opus 4.821.1%SourceClaude Sonnet 4.6—Not directly comparable
OSWorld 2.0
Shared sourceClaude Opus 4.820.6%Claude Sonnet 4.68.3%Claude Opus 4.8 leads this result
Claw-Eval
Claude Opus 4.8—Claude Sonnet 4.667.8%SourceNot directly comparable
CyberGym
Claude Opus 4.8—Claude Sonnet 4.665.2%SourceNot directly comparable
JobBench
Claude Opus 4.8—Claude Sonnet 4.636.9%SourceNot directly comparable
Coding
SWE-bench Verified
Claude Opus 4.888.6%SourceClaude Sonnet 4.679.6%SourceClaude Opus 4.8 leads this result
SWE-bench Pro
Claude Opus 4.869.2%SourceClaude Sonnet 4.6—Not directly comparable
SWE Multilingual
Claude Opus 4.884.4%SourceClaude Sonnet 4.6—Not directly comparable
SWE Multimodal
Claude Opus 4.838.4%SourceClaude Sonnet 4.6—Not directly comparable
Terminal-Bench 2.0
Claude Opus 4.874.6%SourceClaude Sonnet 4.6—Not directly comparable
cursorBench31
Shared sourceClaude Opus 4.858.4%Claude Sonnet 4.648.8%Claude Opus 4.8 leads this result
cursorBench32
Claude Opus 4.862.3%SourceClaude Sonnet 4.6—Not directly comparable
FrontierCode 1.1 Main
Shared sourceClaude Opus 4.846.5%Claude Sonnet 4.624.3%Claude Opus 4.8 leads this result
SWE-Rebench
Claude Opus 4.8—Claude Sonnet 4.660.7%SourceNot directly comparable
React Native Evals
Claude Opus 4.8—Claude Sonnet 4.680.6%SourceNot directly comparable
Vibe Code Bench
Claude Opus 4.8—Claude Sonnet 4.651.48%SourceNot directly comparable
Reasoning
Knowledge
GPQA
Claude Opus 4.893.6%SourceClaude Sonnet 4.689.9%SourceClaude Opus 4.8 leads this result
GPQA-D
Claude Opus 4.893.6%SourceClaude Sonnet 4.6—Not directly comparable
HLE
Claude Opus 4.857.9%SourceClaude Sonnet 4.649%SourceClaude Opus 4.8 leads this result
HLE w/o tools
Claude Opus 4.849.8%SourceClaude Sonnet 4.6—Not directly comparable
SuperGPQA
Claude Opus 4.8—Claude Sonnet 4.695%SourceNot directly comparable
MMLU-Pro
Claude Opus 4.8—Claude Sonnet 4.679.2%SourceNot directly comparable
Math
USAMO 2026
Claude Opus 4.896.7%SourceClaude Sonnet 4.6—Not directly comparable
FrontierMath v2 (Tiers 1-3)
Shared sourceClaude Opus 4.847.241%Claude Sonnet 4.632.400%Claude Opus 4.8 leads this result
FrontierMath v2 (Tier 4)
Shared sourceClaude Opus 4.831.250%Claude Sonnet 4.68.300%Claude Opus 4.8 leads this result
Multilingual
INCLUDE
Claude Opus 4.887.6%SourceClaude Sonnet 4.6—Not directly comparable
Multimodal
OfficeQA Pro
Claude Opus 4.866.2%SourceClaude Sonnet 4.6—Not directly comparable
ScreenSpot Pro
Claude Opus 4.887.9%SourceClaude Sonnet 4.6—Not directly comparable
CharXiv
Claude Opus 4.889.9%SourceClaude Sonnet 4.677.4%SourceClaude Opus 4.8 leads this result
CharXiv w/o tools
Claude Opus 4.880.5%SourceClaude Sonnet 4.6—Not directly comparable
Frequently asked questions
Which is better, Claude Opus 4.8 or Claude Sonnet 4.6?
Claude Opus 4.8 has the higher public score estimate, 76.45 versus 64.62, but the 90% score intervals overlap. The higher estimate is not a decisive winner because the uncertainty ranges overlap.
Which is better for coding, Claude Opus 4.8 or Claude Sonnet 4.6?
The current coding averages use different weighted benchmark sets, so BenchLM does not name a winner from them. Read the shared benchmark rows directly and test the models on the same task set.
Which is better for agentic tasks, Claude Opus 4.8 or Claude Sonnet 4.6?
The current agentic tasks averages use different weighted benchmark sets, so BenchLM does not name a winner from them. Read the shared benchmark rows directly and test the models on the same task set.
Which costs less, Claude Opus 4.8 or Claude Sonnet 4.6?
For the stated presets, chat costs $0.0175 on Claude Opus 4.8 and $0.0105 on Claude Sonnet 4.6; repository review costs $0.325 and $0.195; the cache-heavy agent loop costs $1.35 and $0.81. Claude Sonnet 4.6 does not fit this workload in one request. Claude Opus 4.8 has no published cached-input rate, so cached tokens use its listed input rate. Claude Sonnet 4.6 has no published cached-input rate, so cached tokens use its listed input rate.
Which has the larger context window, Claude Opus 4.8 or Claude Sonnet 4.6?
Claude Opus 4.8 has the larger documented context window: 1M, compared with 200K.
Related comparisons
Last updated August 26, 2026
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