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Claude Fable 5 vs Claude Opus 4.8

Token pricing, context window and real monthly cost, side by side. Claude Opus 4.8 is the cheaper of the two for a typical workload — about 2.0× less.

cheaper for a typical workload
Claude Opus 4.8
saves 50% vs Claude Fable 5 at 1,500 in / 500 out × 200,000/mo
Claude Fable 5 $8,000/mo
Claude Opus 4.8 $4,000/mo
Flagship vs Flagship comparable technical class at a lower rate — the better value

Positioned by published specs — size, context and modality — not measured performance; a smaller model can sometimes outperform a larger one on your task.

Cost versus technical classClaude Fable 5: $8,000/mo, Flagship class. Claude Opus 4.8: $4,000/mo, Flagship class. Plotted by monthly cost (horizontal) against technical class from size and context (vertical).best valuepremiumbudgetoverpricedClaude Fable 5$8,000/mo · FlagshipClaude Opus 4.8$4,000/mo · Flagship← lower cost · monthly $ · higher cost →
↑ technical class (size & context)
Same technical class

Claude Opus 4.8 and Claude Fable 5 are the same class (Flagship) on size & context, so they're plausible substitutes — decide on price, modality and provider fit.

Claude Fable 5 versus Claude Opus 4.8 specifications and price.
metric Claude Fable 5 Claude Opus 4.8
Input / 1M $10.00 $5.00
Output / 1M $50.00 $25.00
Context 1M 1M
Technical class Flagship Flagship
Cost @ typical workload $8,000/mo $4,000/mo
Modality text + image text + image
Price source list list
Provider Anthropic Anthropic

Snapshot . Cost uses a typical workload; tune it in the calculator. How we measure →

Which should you pick?

On a typical workload, Claude Opus 4.8 costs $4,000/mo against Claude Fable 5's $8,000/mo — roughly 2.0× cheaper. But the ranking depends on your output-to-input ratio: output is the pricier direction for both, so an output-heavy job (code generation, long answers) widens the gap while an input-heavy one (summarization, retrieval) narrows it. Both share the same context window, so that's not a deciding factor here. By technical class — a spec read of size and context, not measured capability — both are Flagship, so this is a like-for-like price decision.

These are list and routed market prices, not measured outcomes. Two models at the same rate can still cost different amounts to finish the same task, because verbose or reasoning-heavy models emit more tokens. That gap is exactly what measured cost-per-task captures. The technical-class read above is likewise spec-based — size, context and modality, not measured performance — so a smaller model can still outperform a larger one on your specific task.

Frequently asked questions

Is Claude Fable 5 or Claude Opus 4.8 cheaper?

For a typical workload (1,500 input + 500 output tokens × 200,000 requests/month), Claude Opus 4.8 costs $4,000/mo versus $8,000/mo for Claude Fable 5 — about 2.0× less. Because output is priced higher than input, the winner can flip if your workload writes much more or less than this; check your own numbers in the calculator.

What's the difference between Claude Fable 5 and Claude Opus 4.8 from Anthropic?

Same provider, different tier. On price, Claude Fable 5 is $10.00/$50.00 per 1M (in/out) and Claude Opus 4.8 is $5.00/$25.00. By technical class (size & context) they're the same — both Flagship.

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