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Model A
Claude 3.5 Sonnet

Anthropic

48.68/100

Estimated · Public rank #151

90% interval 37.260.2

Claude 3.5 Sonnet vs Claude 4.1 Opus

Updated September 3, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.

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Model B
Claude 4.1 Opus

Anthropic

44.87/100

Supported · Public rank #178

90% interval 41.848.0

Decision reading

Claude 3.5 Sonnet has the higher public score estimate, 48.68 versus 44.87, but the 90% score intervals overlap. Treat that as a lead, not a settled winner.

1 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.

  • Coding work

    Code generation, repair, and software-engineering tasks

    Claude 4.1 Opus

    Claude 4.1 Opus leads on the same 1 weighted benchmark row.

    Confidence: limited

  • Chat turn cost

    1K fresh input + 500 output tokens

    Claude 3.5 Sonnet

    Claude 3.5 Sonnet 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 3.5 Sonnet

    Claude 3.5 Sonnet has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates

  • Agentic work

    Tool use, computer use, and multi-step task completion

    Not enough matched evidence

    No shared weighted benchmark basis supports a winner.

    Confidence: limited

  • Long documents

    Prompts that approach the documented context limit

    No clear pick

    The documented context windows are equal.

    Confidence: documented

  • 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 3.5 Sonnet does not fit this workload in one request. Claude 4.1 Opus does not fit this workload in one request. Claude 3.5 Sonnet has no published cached-input rate, so cached tokens use its listed input rate. Claude 4.1 Opus 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.

Shared results
1
Claude 3.5 Sonnet only
3
Claude 4.1 Opus only
1
Like-for-like categories
1 / 8

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

Like-for-like
Claude 3.5 Sonnet
49.0
Claude 4.1 Opus
74.5
Weighted basis
1 vs 1 rows
Reading
Claude 4.1 Opus leads

Agentic

Not comparable
Claude 3.5 Sonnet
Not measured
Claude 4.1 Opus
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Reasoning

Not comparable
Claude 3.5 Sonnet
Not measured
Claude 4.1 Opus
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Knowledge

Not comparable
Claude 3.5 Sonnet
59.4
Claude 4.1 Opus
Not measured
Weighted basis
1 vs 0 rows
Reading
Not comparable

Math

Not comparable
Claude 3.5 Sonnet
1.6
Claude 4.1 Opus
Not measured
Weighted basis
2 vs 0 rows
Reading
Not comparable

Multilingual

Not comparable
Claude 3.5 Sonnet
Not measured
Claude 4.1 Opus
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Multimodal

Not comparable
Claude 3.5 Sonnet
Not measured
Claude 4.1 Opus
Not measured
Weighted basis
0 vs 0 rows
Reading
Not comparable

Instruction following

Not comparable
Claude 3.5 Sonnet
Not measured
Claude 4.1 Opus
Not measured
Weighted basis
0 vs 0 rows
Reading
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.

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 3.5 Sonnet
$0.0105
Fits in one request
Claude 4.1 Opus
$0.0525
Fits in one request

Claude 3.5 Sonnet has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

Claude 3.5 Sonnet
$0.195
Fits in one request
Claude 4.1 Opus
$0.975
Fits in one request

Claude 3.5 Sonnet 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 3.5 Sonnet
$0.81
Does not fit in one request
Cached input priced at the published list-input rate
Claude 4.1 Opus
$4.05
Does not fit in one request
Cached input priced at the published list-input rate

Claude 3.5 Sonnet does not fit this workload in one request. Claude 4.1 Opus does not fit this workload in one request. Claude 3.5 Sonnet has no published cached-input rate, so cached tokens use its listed input rate. Claude 4.1 Opus 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.

Context window

Maximum documented context; output-token limits may be lower.

Claude 3.5 Sonnet

200K

Claude 4.1 Opus

200K

API model ID

Claude 3.5 Sonnet

Not sourced

Claude 4.1 Opus

Not sourced

Cached-input rate

A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.

Claude 3.5 Sonnet

Not published

Claude 4.1 Opus

Not published

Documented inputs

Claude 3.5 Sonnet

Not sourced

Claude 4.1 Opus

Not sourced

Documented outputs

Claude 3.5 Sonnet

Not sourced

Claude 4.1 Opus

Not sourced

Provider availability

Claude 3.5 Sonnet

Not sourced

Claude 4.1 Opus

Not sourced

Reasoning profile

Claude 3.5 Sonnet

Non-Reasoning

Claude 4.1 Opus

Non-Reasoning

Weight access

Claude 3.5 Sonnet

Proprietary

Claude 4.1 Opus

Proprietary

License

Claude 3.5 Sonnet

Proprietary

Claude 4.1 Opus

Proprietary

Release date

Claude 3.5 Sonnet

2024-06-01

Claude 4.1 Opus

2025-08-01

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 3.5 Sonnet has the higher public score estimate, 48.68 versus 44.87, but the 90% score intervals overlap.
Workload cost
Repository review: $0.195 vs $0.975. Cache-heavy agent loop: $0.81 vs $4.05.
Context tradeoff
Both models list 200K.

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 evidence5 rows

Agentic

  • JobBench

    Claude 3.5 Sonnet
    Claude 4.1 Opus21.9%
    Source

    Not directly comparable

Coding

  • SWE-bench Verified

    Claude 3.5 Sonnet49%
    Source
    Claude 4.1 Opus74.5%
    Source

    Claude 4.1 Opus leads this result

Knowledge

  • GPQA

    Claude 3.5 Sonnet59.4%
    Source
    Claude 4.1 Opus

    Not directly comparable

Math

  • FrontierMath v2 (Tiers 1-3)

    Claude 3.5 Sonnet2.069%
    Source
    Claude 4.1 Opus

    Not directly comparable

  • FrontierMath v2 (Tier 4)

    Claude 3.5 Sonnet0.000%
    Source
    Claude 4.1 Opus

    Not directly comparable

Frequently asked questions

Which is better, Claude 3.5 Sonnet or Claude 4.1 Opus?

Claude 3.5 Sonnet has the higher public score estimate, 48.68 versus 44.87, 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 3.5 Sonnet or Claude 4.1 Opus?

Claude 4.1 Opus leads the like-for-like coding comparison across 1 shared weighted benchmark row.

Which is better for agentic tasks, Claude 3.5 Sonnet or Claude 4.1 Opus?

The published evidence does not provide a shared weighted agentic tasks basis for both models, so BenchLM does not name a agentic tasks winner.

Which costs less, Claude 3.5 Sonnet or Claude 4.1 Opus?

For the stated presets, chat costs $0.0105 on Claude 3.5 Sonnet and $0.0525 on Claude 4.1 Opus; repository review costs $0.195 and $0.975; the cache-heavy agent loop costs $0.81 and $4.05. Claude 3.5 Sonnet does not fit this workload in one request. Claude 4.1 Opus does not fit this workload in one request. Claude 3.5 Sonnet has no published cached-input rate, so cached tokens use its listed input rate. Claude 4.1 Opus has no published cached-input rate, so cached tokens use its listed input rate.

Which has the larger context window, Claude 3.5 Sonnet or Claude 4.1 Opus?

Both models list the same context window, 200K.

Related comparisons

Last updated September 3, 2026

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