ClaudevsClaude

Claude Sonnet 5 vs Claude Fable 5.1

Side-by-side comparison of pricing, task quality, and projected cost at higher scale.

Pricing

Side-by-side pricing

Claude Sonnet 5

Mid-tier

Claude Fable 5.1

Flagship
Input $/MTok
$2.00
$10.00
Output $/MTok
$10.00
$50.00
Cache discount
90% off
98% off
Context
1M
1M

Quality

Task confidence comparison

Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
68
vs
74
Code Review
96
vs
0
Summarization
64
vs
71
Q&A
89
vs
0
Extraction
70
vs
75
Reasoning
89
vs
92
Classification
86
vs
0
Creative Writing
62
vs
78
Claude Sonnet 5
Claude Fable 5.1

Guidance

When to use Claude Sonnet 5 vs Claude Fable 5.1

Choose Claude Sonnet 5 when...

  • -Cost matters: 80% cheaper on input tokens

Choose Claude Fable 5.1 when...

  • -You need strong reasoning (confidence 92 vs 89)
  • -You need strong creative writing (confidence 78 vs 62)
  • -You need strong extraction (confidence 75 vs 70)
  • -You need strong code generation (confidence 74 vs 68)

At scale

Cost at scale

Estimated cost assuming a seventy percent input and thirty percent output token split.
Claude Sonnet 5
Claude Fable 5.1
100K tokens
$0.44Cheaper
$2.20
1M tokens
$4.40Cheaper
$22.00
10M tokens
$44.00Cheaper
$220.00

FAQ

When should I use Claude Sonnet 5 instead of Claude Fable 5.1?

Claude Sonnet 5 and Claude Fable 5.1 perform similarly across all tracked tasks. Pick based on pricing and provider preference.

Is Claude Fable 5.1 cheaper than Claude Sonnet 5?

Claude Fable 5.1 input costs $10.00/MTok, which is 400% more than Claude Sonnet 5 at $2.00/MTok.

What are the context window sizes for Claude Sonnet 5 and Claude Fable 5.1?

Claude Sonnet 5 has a 1M token context window. Claude Fable 5.1 has a 1M token context window.

Track your real costs

Comparisons show estimated costs at list price. The dashboard reveals your real spend and savings.