Claude Fable 5 vs Gemini 3.1 Flash Lite

Anthropic · US  |  Google · US · Updated June 2026

Quick verdict

Pick Claude Fable 5 for the hardest reasoning and most complex problems or long-horizon, multi-step agentic work. Pick Gemini 3.1 Flash Lite for ultra-low-latency, high-volume production workloads or most cost-efficient gemini 3 model — half the price of gemini 3 flash ($0.25/$1.50 vs $0.50/$3.00 per 1m tokens). On a tight budget at scale, Gemini 3.1 Flash Lite is the value pick.

Claude Fable 5 (Anthropic) and Gemini 3.1 Flash Lite (Google) are two of the models people most often weigh against each other in 2026. 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. Gemini 3.1 Flash Lite is google's fastest and most cost-efficient Gemini 3 series model, built for ultra-low-latency, high-volume production workloads at half the price of Gemini 3 Flash. Their biggest split is price, and the breakdown below shows exactly how that plays out for your workload.

Key differences at a glance

Side-by-side specs

SpecClaude Fable 5Gemini 3.1 Flash Lite
ProviderAnthropic (US) Google (US)
ReleasedJune 9, 2026 March 3, 2026
Context window1M (~1,500 pages) 1M (~1,500 pages)
Price (in/out)$10/$50 per 1M tokens $0.25/$1.5 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, audio, video
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published 12.3%

Who wins what

The hardest reasoning and most complex problems

Claude Fable 5

A core design strength of Claude Fable 5.

Long-horizon, multi-step agentic work

Claude Fable 5

A core design strength of Claude Fable 5.

Frontier-level analysis and research

Claude Fable 5

A core design strength of Claude Fable 5.

Ultra-low-latency, high-volume production workloads

Gemini 3.1 Flash Lite

A core design strength of Gemini 3.1 Flash Lite.

Most cost-efficient Gemini 3 model — half the price of Gemini 3 Flash ($0.25/$1.50 vs $0.50/$3.00 per 1M tokens)

Gemini 3.1 Flash Lite

A core design strength of Gemini 3.1 Flash Lite.

High-volume agentic and tool-calling loops where cost per call matters

Gemini 3.1 Flash Lite

A core design strength of Gemini 3.1 Flash Lite.

Lowest cost at scale

Gemini 3.1 Flash Lite

At $0.25/$1.5 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

Gemini 3.1 Flash Lite

At $0.25/$1.5 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 ultra-low-latency, high-volume production workloads

Gemini 3.1 Flash Lite

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.

Gemini 3.1 Flash Lite: where it fits

Google's fastest and most cost-efficient Gemini 3 series model, built for ultra-low-latency, high-volume production workloads at half the price of Gemini 3 Flash. Released March 3, 2026 by Google, it is built for ultra-low-latency, high-volume production workloads, most cost-efficient Gemini 3 model — half the price of Gemini 3 Flash ($0.25/$1.50 vs $0.50/$3.00 per 1M tokens), high-volume agentic and tool-calling loops where cost per call matters, and multimodal input across text, image, video, audio, and PDF.

Its trade-offs: lower reasoning and quality ceiling than Gemini 3.1 Pro and the full Gemini 3 Flash tier, sharp long-context degradation — MRCR v2 (8-needle) retrieval falls to ~12% at the full 1M-token window, and closed weights — not downloadable or self-hostable. At $0.25 in / $1.5 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

Claude Fable 5 and Gemini 3.1 Flash Lite overlap enough that the right pick depends on your specific job. Gemini 3.1 Flash Lite costs less per token; and each leads in its own area — Claude Fable 5 for the hardest reasoning and most complex problems, Gemini 3.1 Flash Lite for ultra-low-latency, high-volume production workloads. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Claude Fable 5 and Gemini 3.1 Flash Lite without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Claude Fable 5 or Gemini 3.1 Flash Lite 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 Gemini 3.1 Flash Lite leans toward ultra-low-latency, high-volume production workloads, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Fable 5 or Gemini 3.1 Flash Lite?

Gemini 3.1 Flash Lite is cheaper — $10/$50 per 1M tokens vs $0.25/$1.5 per 1M tokens, roughly 40× apart on input.

Which has the bigger context window?

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

Can I use both Claude Fable 5 and Gemini 3.1 Flash Lite together?

Yes — a multi-model platform like LumiChats gives you Claude Fable 5, Gemini 3.1 Flash Lite and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Claude Fable 5 or Gemini 3.1 Flash Lite?

Claude Fable 5 — released June 9, 2026, about 3 months after Gemini 3.1 Flash Lite.

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.