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Model A
Claude 3.5 Sonnet

Anthropic

31.93/100

Supported · Public rank #220

90% interval 22.940.9

Claude 3.5 Sonnet vs Claude Fable 5

Updated September 4, 2026. Public scores include evidence status and uncertainty. They are not guarantees for a specific workload.

Anthropic logo
Model B
Claude Fable 5

Anthropic

80.9/100

Supported · Public rank #3

90% interval 78.783.1

Decision reading

Claude Fable 5 has the higher public score, 80.9 versus 31.93, and the 90% score intervals do not overlap.

1 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

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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 Fable 5

    Claude Fable 5 has the larger documented context window.

    Confidence: documented

  • 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

  • Coding work

    Code generation, repair, and software-engineering tasks

    Not enough matched evidence

    Claude 3.5 Sonnet is not ranked on the public lane for coding, so no winner is named for coding.

    Confidence: limited

  • Agentic work

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

    Not enough matched evidence

    Claude 3.5 Sonnet is not ranked on the public lane for agentic, so no winner is named for agentic.

    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 3.5 Sonnet 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.

    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 Fable 5 only
17
Like-for-like categories
0 / 8

Category results, on a stated basis

Each row shows the public-lane category score for both models: the BenchAlign lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.

Agentic

Not comparable
Claude 3.5 Sonnet
Not ranked
Claude Fable 5
74.8
Supported · #3/151
Basis
BenchAlign lane · 0 vs 4 public rows
Reading
Not comparable

Coding

Not comparable
Claude 3.5 Sonnet
Not ranked
Claude Fable 5
76.9
Supported · #2/183
Basis
BenchAlign lane · 1 vs 10 public rows
Reading
Not comparable

Reasoning

Not comparable
Claude 3.5 Sonnet
Not ranked
Claude Fable 5
76.2
#11/22
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Knowledge

Not comparable
Claude 3.5 Sonnet
Not ranked
Claude Fable 5
83.5
Supported · #2/181
Basis
BenchAlign lane · 1 vs 2 public rows
Reading
Not comparable

Math

Not comparable
Claude 3.5 Sonnet
25.7
Unranked · 2 rankable rows
Claude Fable 5
Not ranked
Basis
Provisional lane · 2 vs 0 weighted rows
Reading
Not comparable

Multilingual

Not comparable
Claude 3.5 Sonnet
Not ranked
Claude Fable 5
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multimodal

Not comparable
Claude 3.5 Sonnet
Not ranked
Claude Fable 5
62.5
Unranked · 2 rankable rows
Basis
Provisional lane · 0 vs 1 weighted rows
Reading
Not comparable

Instruction following

Not comparable
Claude 3.5 Sonnet
Not ranked
Claude Fable 5
78.3
#54/120
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign) differ from the provisional-lane categories. Unranked scores sit on the lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.

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 Fable 5
$0.035
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 Fable 5
$0.65
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 Fable 5
$0.9
Fits in one request

Claude 3.5 Sonnet 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.

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 Fable 5

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 Fable 5

$1 per 1M cached input tokens

Claude API pricing

Provider availability

Claude 3.5 Sonnet

Not sourced

Claude Fable 5

Generally Available · Claude API

Anthropic model overview

Reasoning profile

Claude 3.5 Sonnet

Non-Reasoning

Claude Fable 5

Reasoning

Weight access

Claude 3.5 Sonnet

Proprietary

Claude Fable 5

Proprietary

License

Claude 3.5 Sonnet

Proprietary

Claude Fable 5

Proprietary

Release date

Claude 3.5 Sonnet

2024-06-01

Claude Fable 5

2026-06-09

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 Fable 5 has the higher public score, 80.9 versus 31.93, and the 90% score intervals do not overlap.
Workload cost
Repository review: $0.195 vs $0.65. Cache-heavy agent loop: $0.81 vs $0.9.
Context tradeoff
Claude Fable 5 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 evidence21 rows

Agentic

  • Terminal-Bench 3.0

    Claude 3.5 Sonnet
    Claude Fable 534.0%
    Source

    Not directly comparable

  • Terminal-Bench 2.0

    Claude 3.5 Sonnet
    Claude Fable 584.3%
    Source

    Not directly comparable

  • OSWorld-Verified

    Claude 3.5 Sonnet
    Claude Fable 585%
    Source

    Not directly comparable

  • Terminal-Bench 2.1 (Vals)

    Claude 3.5 Sonnet
    Claude Fable 580.5%
    Source

    Not directly comparable

Coding

  • SWE-bench Verified

    Claude 3.5 Sonnet49%
    Source
    Claude Fable 595%
    Source

    Claude Fable 5 leads this result

  • SWE-bench Pro

    Claude 3.5 Sonnet
    Claude Fable 580%
    Source

    Not directly comparable

  • FrontierSWE v2

    Claude 3.5 Sonnet
    Claude Fable 548.0%
    Source

    Not directly comparable

  • FrontierCode 1.1 Main

    Claude 3.5 Sonnet
    Claude Fable 553.5%
    Source

    Not directly comparable

  • Terminal-Bench 2.0

    Claude 3.5 Sonnet
    Claude Fable 584.3%
    Source

    Not directly comparable

  • cursorBench31

    Claude 3.5 Sonnet
    Claude Fable 570.6%
    Source

    Not directly comparable

  • cursorBench32

    Claude 3.5 Sonnet
    Claude Fable 570.5%
    Source

    Not directly comparable

  • VulcanBench v3

    Claude 3.5 Sonnet
    Claude Fable 589.5%
    Source

    Not directly comparable

  • LiveCodeBench (Vals)

    Claude 3.5 Sonnet
    Claude Fable 589.8%
    Source

    Not directly comparable

  • SWE-bench (Vals)

    Claude 3.5 Sonnet
    Claude Fable 595.0%
    Source

    Not directly comparable

Knowledge

  • GPQA

    Claude 3.5 Sonnet59.4%
    Source
    Claude Fable 5

    Not directly comparable

  • GPQA Diamond (Vals)

    Claude 3.5 Sonnet
    Claude Fable 593.2%
    Source

    Not directly comparable

  • MMLU-Pro (Vals)

    Claude 3.5 Sonnet
    Claude Fable 591.5%
    Source

    Not directly comparable

Math

  • FrontierMath v2 (Tiers 1-3)

    Claude 3.5 Sonnet2.069%
    Source
    Claude Fable 5

    Not directly comparable

  • FrontierMath v2 (Tier 4)

    Claude 3.5 Sonnet0.000%
    Source
    Claude Fable 5

    Not directly comparable

Multimodal

  • Blueprint-Bench 2

    Claude 3.5 Sonnet
    Claude Fable 538.6%
    Source

    Not directly comparable

  • OfficeQA Pro

    Claude 3.5 Sonnet
    Claude Fable 557.9%
    Source

    Not directly comparable

Frequently asked questions

Which is better, Claude 3.5 Sonnet or Claude Fable 5?

Claude Fable 5 has the higher public score, 80.9 versus 31.93, and the 90% score intervals do not overlap. That is the clearest overall quality signal in the current public data.

Which is better for coding, Claude 3.5 Sonnet or Claude Fable 5?

Claude 3.5 Sonnet is not ranked on the public lane for coding, so no winner is named for coding.

Which is better for agentic tasks, Claude 3.5 Sonnet or Claude Fable 5?

Claude 3.5 Sonnet is not ranked on the public lane for agentic tasks, so no winner is named for agentic tasks.

Which costs less, Claude 3.5 Sonnet or Claude Fable 5?

For the stated presets, chat costs $0.0105 on Claude 3.5 Sonnet and $0.035 on Claude Fable 5; repository review costs $0.195 and $0.65; the cache-heavy agent loop costs $0.81 and $0.9. Claude 3.5 Sonnet 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.

Which has the larger context window, Claude 3.5 Sonnet or Claude Fable 5?

Claude Fable 5 has the larger documented context window: 1M, compared with 200K.

Related comparisons

Last updated September 4, 2026

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