Roboflow

Claude Fable 5.2 vs Claude Sonnet 5.5

Claude Fable 5.2 and Claude Sonnet 5.5 score 86.5% vs 77.6% averaged across five Vision Evals tasks (#2 and #12 of 67 models), so Claude Fable 5.2 leads overall.

  • Claude Fable 5.2 wins all 5 tasks, with its widest lead on OCR (79.5% vs 66.3%).
  • Claude Sonnet 5.5 is about a quarter of the cost: $0.0073 vs $0.031 overall average cost per sample.
  • Claude Sonnet 5.5 is faster: 8.3s vs 9.3s per sample.

Compare Claude Fable 5.2 vs Claude Sonnet 5.5 live

Run the same image across every model that supports a task and compare their outputs side-by-side.

These models don't share enough common tasks for a side-by-side demo. See the comparison table below for their capabilities.

Claude Fable 5.2 vs Claude Sonnet 5.5 on Vision Evals

Score by taskClaude Fable 5.2Claude Sonnet 5.5
OCR
79.5
66.3
Reasoning
88.1
76.4
Object Detection
81.6
74.3
Counting
86.5
79.3
Identification
96.9
91.7

Roboflow Vision Evals. Full breakdown below.

Claude Fable 5.2 vs Claude Sonnet 5.5 Comparison Table

Evals updated November 10, 2026Pricing updated November 10, 2026

PropertyClaude Fable 5.2Claude Sonnet 5.5
OrganizationAnthropicAnthropic
Categoryclosedclosed
Modalitymultimodalmultimodal
Release DateNov 2026Sep 2026
Context Window1.0M1.0M
ParametersUnknownUnknown
LicenseProprietaryProprietary
Commercial usecommercial use per vendor termscommercial use per vendor terms
Pricing per 1M tokens
Input $/1M$8.00$2.00
Output $/1M$40.00$10.00
Vision Tasks
CaptioningSupportedDemo
ClassificationSupportedDemo
Object DetectionSupportedDemo
OCRSupportedDemo
Visual Question AnsweringSupportedDemo
Both support 5 more tasks
Model Features
Both support 3 more features
Vision Evalsground-truth scores across 5 vision tasks, pooled at low effort
Overall
86.5%
77.6%
Avg cost / sample$0.031$0.0073
Avg speed / sample9.33s8.33s
By task
Object Detection (low)
81.6%
±0.3, Mean of 3 runs, range 81.2 to 81.9
$0.048
74.3%
±0.9, Mean of 3 runs, range 73.5 to 75.3
$0.0098
Object Detection (high)
83.3%
±0.5, Mean of 3 runs, range 82.8 to 83.7
$0.055
76.8%
±0.4, Mean of 3 runs, range 76.5 to 77.3
$0.014
Counting (low)
86.5%
±0.0, Mean of 3 runs, range 86.5 to 86.5
$0.015
79.3%
±0.7, Mean of 3 runs, range 78.4 to 79.7
$0.0042
Counting (high)
92.8%
±1.4, Mean of 3 runs, range 91.9 to 94.6
$0.021
82.9%
±1.4, Mean of 3 runs, range 81.1 to 83.8
$0.0053
Identification (low)
96.9%
±0.0, Mean of 3 runs, range 96.9 to 96.9
$0.011
91.7%
±3.1, Mean of 3 runs, range 87.5 to 93.8
$0.0029
Identification (high)
94.8%
±1.6, Mean of 3 runs, range 93.8 to 96.9
$0.012
90.6%
±0.0, Mean of 3 runs, range 90.6 to 90.6
$0.0033
OCR (low)
79.5%
$0.030
66.3%
$0.0075
by category
Single value
64.8%
Transcription
94.7%
Structured JSON
92.8%
Text localization
74.5%
Single value
48.7%
Transcription
76.3%
Structured JSON
83.8%
Text localization
60.6%
OCR (high)
84.8%
$0.043
–
by category
Single value
77.4%
Transcription
97.9%
Structured JSON
94.1%
Text localization
72.9%
Reasoning (low)
88.1%
±1.3, Mean of 3 runs, range 86.8 to 89.4
$0.016
76.4%
±0.7, Mean of 3 runs, range 75.5 to 76.8
$0.0049
Reasoning (high)
92.0%
±1.0, Mean of 3 runs, range 91.4 to 93.4
$0.024
83.9%
±1.7, Mean of 3 runs, range 82.1 to 85.4
$0.0061

Claude Fable 5.2 vs Claude Sonnet 5.5: Overview

Claude Fable 5.2

Claude Fable 5.2 is a proprietary multimodal model from Anthropic, released on November 9, 2026. It accepts text and images and produces text, with a one million token context window and up to 128,000 output tokens. Adaptive thinking is always enabled, with an effort setting that controls reasoning. Anthropic positions Fable for demanding reasoning and long-running technical work, including coding and analysis of visual inputs.

Fable 5.2 succeeds Fable 5.1. Anthropic reports improvements in coding, reasoning, and vision, with output generation up to 30% faster than its predecessor. Fable and Mythos 5.2 share an underlying model, with additional cybersecurity and biology safeguards applied to Fable. Model weights are not publicly released.

Claude Sonnet 5.5

Claude Sonnet 5.5 is a proprietary multimodal language model from Anthropic and the second release in the Claude 5.5 family, following Claude Opus 5.5. It accepts interleaved text and image input and returns text, operating with a 1M token context window and a maximum output of 128K tokens per request. The model uses adaptive thinking by default, allocating variable reasoning effort per request rather than exposing a manual extended thinking toggle, and its training data cutoff is June 2026. Anthropic positions it as a faster, lower cost complement to Opus 5.5 for well scoped everyday tasks, bug fixing, and producing documents, slides, and spreadsheets.

Anthropic describes it as the first Sonnet model able to complete Pokemon Red from screenshots alone, and it generates output more than 30% faster than Sonnet 5 while using fewer tokens for equivalent work.

Frequently Asked Questions

On Roboflow's Vision Evals, Claude Fable 5.2 performed better. It scores higher on all five vision tasks and averages 86.5% (#2 of 67) against 77.6% (#12 of 67) for Claude Sonnet 5.5. These scores measure vision capabilities only; either model may perform differently on work outside this benchmark's tasks.

Yes. On the Vision Evals OCR benchmark at low effort, Claude Fable 5.2 leads with 79.5% against 66.3%. This is the widest gap between the two models across the benchmark's tasks.

Claude Sonnet 5.5 is cheaper to run. Across Roboflow's Vision Evals task mix it averaged $0.0073 per sample against $0.031. Claude Fable 5.2 is priced at $8.00 per 1M input tokens and $40.00 per 1M output; Claude Sonnet 5.5 is priced at $2.00 per 1M input tokens and $10.00 per 1M output. Actual costs depend on your image sizes, prompts, and output length.

Claude Sonnet 5.5 is faster. Across Roboflow's Vision Evals it averaged 8.3s per inference against 9.3s. Latency varies with image size, prompt length, and provider load, so treat these as relative rather than guaranteed figures.