Claude Fable 5 vs Claude Opus 5

Anthropic · US  |  Anthropic · US · Updated June 2026

Quick verdict

Both are Anthropic models. Claude Opus 5 is the newer, generally stronger default; reach for Claude Fable 5 when a specific cost or latency profile matters more than the latest capabilities.

Claude Fable 5 and Claude Opus 5 are both Anthropic models, so the real question is not which lab to trust but which tier fits your workload and budget. Claude Fable 5 is anthropic's top public Mythos-class model and its most capable yet, though tier access was temporarily suspended in June 2026 under a US export-control directive. Claude Opus 5 is anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. Since both come from the same lab, the comparison below focuses on the tier-and-cost trade-offs that actually separate them.

Key differences at a glance

Side-by-side specs

SpecClaude Fable 5Claude Opus 5
ProviderAnthropic (US) Anthropic (US)
ReleasedJune 9, 2026 July 24, 2026
Context window1M (~1,500 pages) 1M (~1,500 pages)
Price (in/out)$10/$50 per 1M tokens $5/$25 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

The hardest reasoning and most complex problems

Claude Fable 5

Claude Fable 5 lists the hardest reasoning and most complex problems among its strengths; Claude Opus 5 does not.

Long-horizon, multi-step agentic work

Claude Fable 5

Claude Fable 5 lists long-horizon, multi-step agentic work among its strengths; Claude Opus 5 does not.

Frontier-level analysis and research

Claude Fable 5

Claude Opus 5 is comparatively weak here — behind Mythos 5 on cybersecurity exploitation and biology research, by Anthropic's own account

Frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1

Claude Opus 5

At $5/$25 per 1M tokens it undercuts Claude Fable 5 ($10/$50 per 1M tokens), and that gap compounds at volume.

Agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures)

Claude Opus 5

Anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak — and it runs cheaper at $5/$25 per 1M tokens.

Computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost

Claude Opus 5

Anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak — and it is the newer of the two.

Lowest cost at scale

Claude Opus 5

At $5/$25 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Which should you pick?

A cost-sensitive startup shipping high volume

Claude Opus 5

At $5/$25 per 1M tokens it undercuts Claude Fable 5, and on millions of tokens that margin decides the monthly bill.

Anyone whose priority is the hardest reasoning and most complex problems

Claude Fable 5

It is specifically built for that.

Anyone whose priority is frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1

Claude Opus 5

That is its strongest area.

Claude Fable 5: where it fits

Anthropic's top public Mythos-class model and its most capable yet, though tier access was temporarily suspended in June 2026 under a US export-control directive. Released June 9, 2026 by Anthropic, it is built for the hardest reasoning and most complex problems, long-horizon, multi-step agentic work, frontier-level analysis and research, and work where maximum capability outweighs cost.

Its trade-offs are real: highest price in the Claude lineup, and tier access was temporarily suspended in June 2026 under a US export-control directive. At $10 in / $50 out per million tokens, it sits in the premium price band.

Claude Opus 5: where it fits

Anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. Released July 24, 2026 by Anthropic, it is built for frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1, agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures), computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost, and a native effort setting (low, medium, high, xhigh, max) that trades token cost against capability on a single model.

Its trade-offs: behind Mythos 5 on cybersecurity exploitation and biology research, by Anthropic's own account, all launch benchmarks are Anthropic-reported and not yet independently reproduced, no published SWE-Bench Verified score, so head-to-head coding comparisons rely on Anthropic's own benchmark suite, and fast mode's throughput costs double the base price ($10/$50 per 1M). At $5 in / $25 out per million tokens, it sits in the premium price band.

The bottom line for this matchup

Because Claude Fable 5 and Claude Opus 5 come from the same lab (Anthropic), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. Claude Opus 5 is the more capable, more recent option; the other earns its place only when its price or latency profile fits a specific job better. Most teams should default to Claude Opus 5 and drop down only with a concrete reason.

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See pricing

Frequently asked questions

Is Claude Fable 5 or Claude Opus 5 better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Claude Fable 5 leans toward the hardest reasoning and most complex problems while Claude Opus 5 leans toward frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Fable 5 or Claude Opus 5?

Claude Opus 5 is cheaper — $10/$50 per 1M tokens vs $5/$25 per 1M tokens, roughly 2× apart on input.

Which has the bigger context window?

Both advertise 1M (~1,500 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.

Should I upgrade from Claude Fable 5 to Claude Opus 5?

Since both are Anthropic models, the newer one (Claude Opus 5) is usually the better default unless you need a specific cost or latency profile from the other.

Which is newer, Claude Fable 5 or Claude Opus 5?

Claude Opus 5 — released July 24, 2026, about 45 days after Claude Fable 5.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.