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Model A
Claude Fable 5

Anthropic

80.9/100

Supported · Public rank #3

90% interval 78.783.1

Claude Fable 5 vs o3-mini

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

OpenAI logo
Model B
o3-mini

OpenAI

48.06/100

Supported · Public rank #153

90% interval 37.758.4

Decision reading

Claude Fable 5 has the higher public score, 80.9 versus 48.06, 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.

  • Coding work

    Code generation, repair, and software-engineering tasks

    Claude Fable 5

    Claude Fable 5 leads on the public coding lane, 76.9 to 40.6, with Supported evidence for both models and non-overlapping 90% intervals.

    Confidence: stronger

  • 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

    o3-mini

    o3-mini 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

    o3-mini

    o3-mini 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

    O3-mini 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. o3-mini does not fit this workload in one request. o3-mini 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 Fable 5 only
17
o3-mini only
4
Like-for-like categories
2 / 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.

Coding

Like-for-like
Claude Fable 5
76.9
Supported · #2/183
o3-mini
40.6
Supported · #140/183
Basis
BenchAlign lane · 10 vs 1 public rows
Reading
Claude Fable 5 leads

Knowledge

Like-for-like
Claude Fable 5
83.5
Supported · #2/181
o3-mini
42.3
Supported · #127/181
Basis
BenchAlign lane · 2 vs 2 public rows
Reading
Claude Fable 5 leads

Agentic

Not comparable
Claude Fable 5
74.8
Supported · #3/151
o3-mini
Not ranked
Basis
BenchAlign lane · 4 vs 0 public rows
Reading
Not comparable

Reasoning

Not comparable
Claude Fable 5
76.2
#11/22
o3-mini
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Math

Not comparable
Claude Fable 5
Not ranked
o3-mini
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multilingual

Not comparable
Claude Fable 5
Not ranked
o3-mini
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multimodal

Not comparable
Claude Fable 5
62.5
Unranked · 2 rankable rows
o3-mini
Not ranked
Basis
Provisional lane · 1 vs 0 weighted rows
Reading
Not comparable

Instruction following

Not comparable
Claude Fable 5
78.3
#54/120
o3-mini
Not ranked
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 Fable 5
$0.035
Fits in one request
o3-mini
$0.0033
Fits in one request

o3-mini has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

Claude Fable 5
$0.65
Fits in one request
o3-mini
$0.0682
Fits in one request

o3-mini 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 Fable 5
$0.9
Fits in one request
o3-mini
$0.286
Does not fit in one request
Cached input priced at the published list-input rate

o3-mini does not fit this workload in one request. o3-mini 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 Fable 5

o3-mini

200K

Cached-input rate

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

Claude Fable 5

$1 per 1M cached input tokens

Claude API pricing

o3-mini

Not published

Reasoning profile

Claude Fable 5

Reasoning

o3-mini

Reasoning

Weight access

Claude Fable 5

Proprietary

o3-mini

Proprietary

License

Claude Fable 5

Proprietary

o3-mini

Proprietary

Release date

Claude Fable 5

2026-06-09

o3-mini

2025-01-31

If you already use one of these models
Deployment change
The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
Quality signal
Claude Fable 5 has the higher public score, 80.9 versus 48.06, and the 90% score intervals do not overlap.
Workload cost
Repository review: $0.65 vs $0.0682. Cache-heavy agent loop: $0.9 vs $0.286.
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 evidence22 rows

Agentic

  • Terminal-Bench 3.0

    Claude Fable 534.0%
    Source
    o3-mini

    Not directly comparable

  • Terminal-Bench 2.0

    Claude Fable 584.3%
    Source
    o3-mini

    Not directly comparable

  • OSWorld-Verified

    Claude Fable 585%
    Source
    o3-mini

    Not directly comparable

  • Terminal-Bench 2.1 (Vals)

    Claude Fable 580.5%
    Source
    o3-mini

    Not directly comparable

Coding

  • SWE-bench Verified

    Claude Fable 595%
    Source
    o3-mini49.3%
    Source

    Claude Fable 5 leads this result

  • SWE-bench Pro

    Claude Fable 580%
    Source
    o3-mini

    Not directly comparable

  • FrontierSWE v2

    Claude Fable 548.0%
    Source
    o3-mini

    Not directly comparable

  • FrontierCode 1.1 Main

    Claude Fable 553.5%
    Source
    o3-mini

    Not directly comparable

  • Terminal-Bench 2.0

    Claude Fable 584.3%
    Source
    o3-mini

    Not directly comparable

  • cursorBench31

    Claude Fable 570.6%
    Source
    o3-mini

    Not directly comparable

  • cursorBench32

    Claude Fable 570.5%
    Source
    o3-mini

    Not directly comparable

  • VulcanBench v3

    Claude Fable 589.5%
    Source
    o3-mini

    Not directly comparable

  • LiveCodeBench (Vals)

    Claude Fable 589.8%
    Source
    o3-mini

    Not directly comparable

  • SWE-bench (Vals)

    Claude Fable 595.0%
    Source
    o3-mini

    Not directly comparable

Knowledge

  • GPQA Diamond (Vals)

    Claude Fable 593.2%
    Source
    o3-mini

    Not directly comparable

  • MMLU-Pro (Vals)

    Claude Fable 591.5%
    Source
    o3-mini

    Not directly comparable

  • MMLU

    Claude Fable 5
    o3-mini86.9%
    Source

    Not directly comparable

  • GPQA

    Claude Fable 5
    o3-mini77.2%
    Source

    Not directly comparable

Math

  • AIME 2024

    Claude Fable 5
    o3-mini87.3%
    Source

    Not directly comparable

Multimodal

  • Blueprint-Bench 2

    Claude Fable 538.6%
    Source
    o3-mini

    Not directly comparable

  • OfficeQA Pro

    Claude Fable 557.9%
    Source
    o3-mini

    Not directly comparable

Instruction following

  • IFEval

    Claude Fable 5
    o3-mini93.9%
    Source

    Not directly comparable

Frequently asked questions

Which is better, Claude Fable 5 or o3-mini?

Claude Fable 5 has the higher public score, 80.9 versus 48.06, 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 Fable 5 or o3-mini?

Claude Fable 5 leads the public coding lane, 76.9 to 40.6, with Supported evidence for both models and non-overlapping 90% intervals.

Which is better for agentic tasks, Claude Fable 5 or o3-mini?

O3-mini is not ranked on the public lane for agentic tasks, so no winner is named for agentic tasks.

Which costs less, Claude Fable 5 or o3-mini?

For the stated presets, chat costs $0.035 on Claude Fable 5 and $0.0033 on o3-mini; repository review costs $0.65 and $0.0682; the cache-heavy agent loop costs $0.9 and $0.286. o3-mini does not fit this workload in one request. o3-mini has no published cached-input rate, so cached tokens use its listed input rate.

Which has the larger context window, Claude Fable 5 or o3-mini?

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

Related comparisons

Last updated September 4, 2026

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