Claude Fable 5.1 vs Hunyuan Hy3

Anthropic · US  |  Tencent · China · Updated June 2026

Quick verdict

Pick Claude Fable 5.1 for terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%) or cursorbench 3.2 agentic coding (73.4%). Pick Hunyuan Hy3 for frontier-level reported reasoning and science (gpqa diamond 90.4) at low active-parameter cost or runs a 295b model at the cost of a 21b — only 21b parameters active per token. Choose Hunyuan Hy3 if you need self-hosting or data privacy; Claude Fable 5.1 if you want a managed API.

Claude Fable 5.1 (Anthropic, US) and Hunyuan Hy3 (Tencent, China) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. Claude Fable 5.1 is anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores. Hunyuan Hy3 is a 295B Apache-2.0 open MoE that reaches frontier reasoning quality while running at roughly 21B active-parameter cost. They diverge most on price, context window and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecClaude Fable 5.1Hunyuan Hy3
ProviderAnthropic (US) Tencent (China)
ReleasedSeptember 1, 2026 July 6, 2026
Context window1M tokens (~1,500 pages) 256K (~384 pages)
Price (in/out)$10/$50 per 1M tokens Open weight (self-host / free)
Open weight?No — API only Yes — self-hostable
Modalitiestext, image text, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Terminal-Bench-Science agentic research (52.6%, more than double Fable 5's 24.7%)

Claude Fable 5.1

Hunyuan Hy3 is comparatively weak here — benchmarks are largely self-reported, and the ultra-low hosted pricing is a limited promotion

CursorBench 3.2 agentic coding (73.4%)

Claude Fable 5.1

Anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores — and it carries the larger 1M tokens context.

Cache-read pricing cut to a quarter of other Claude models

Claude Fable 5.1

Anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores — and it is the newer of the two.

Frontier-level reported reasoning and science (GPQA Diamond 90.4) at low active-parameter cost

Hunyuan Hy3

A 295B Apache-2.0 open MoE that reaches frontier reasoning quality while running at roughly 21B active-parameter cost — and its weights are open while Claude Fable 5.1 is API-only.

Runs a 295B model at the cost of a 21B — only 21B parameters active per token

Hunyuan Hy3

Claude Fable 5.1 is comparatively weak here — anthropic has not published an official SWE-bench Verified score for this model

Clean, unrestricted Apache-2.0 license with no geographic carve-out

Hunyuan Hy3

Hunyuan Hy3 lists clean, unrestricted Apache-2.0 license with no geographic carve-out among its strengths; Claude Fable 5.1 does not.

Lowest cost at scale

Hunyuan Hy3

Its weights are open, so at volume you pay for your own hardware instead of Claude Fable 5.1's $10/$50 per 1M tokens.

Largest single-prompt input

Claude Fable 5.1

Its 1M tokens window is about 3.9× larger than Hunyuan Hy3's 256K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Hunyuan Hy3

At Open weight (self-host / free) it undercuts Claude Fable 5.1, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Claude Fable 5.1

Larger 1M tokens window fits more in one prompt.

A team with data-privacy or self-hosting needs

Hunyuan Hy3

Open weights let you run it on your own hardware; Claude Fable 5.1 is API-only.

Anyone whose priority is terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%)

Claude Fable 5.1

It is specifically built for that.

Anyone whose priority is frontier-level reported reasoning and science (gpqa diamond 90.4) at low active-parameter cost

Hunyuan Hy3

That is its strongest area.

An enterprise with regional data-residency rules

Claude Fable 5.1 or Hunyuan Hy3

Origin (US vs China) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

Claude Fable 5.1: where it fits

Anthropic's September 1, 2026 update to its Fable line for coding and knowledge work, keeping the 1M-token context of Fable 5 while cutting cache-read costs and roughly doubling agentic-research benchmark scores. Released September 1, 2026 by Anthropic, it is built for terminal-Bench-Science agentic research (52.6%, more than double Fable 5's 24.7%), cursorBench 3.2 agentic coding (73.4%), cache-read pricing cut to a quarter of other Claude models, and long, multistep, document-heavy professional work with 1M-token context.

Its trade-offs are real: anthropic has not published an official SWE-bench Verified score for this model, restricted Mythos 5.1 variant outscores it on some benchmarks due to lighter safeguards (Terminal-Bench 4.0: 60.9% vs 55.8%), and closed weights, no self-hosting option. At $10 in / $50 out per million tokens, it sits in the premium price band.

Hunyuan Hy3: where it fits

A 295B Apache-2.0 open MoE that reaches frontier reasoning quality while running at roughly 21B active-parameter cost. Released July 6, 2026 by Tencent, it is built for frontier-level reported reasoning and science (GPQA Diamond 90.4) at low active-parameter cost, runs a 295B model at the cost of a 21B — only 21B parameters active per token, clean, unrestricted Apache-2.0 license with no geographic carve-out, and broad day-one ecosystem support plus an FP8 checkpoint.

Its trade-offs: benchmarks are largely self-reported, and the ultra-low hosted pricing is a limited promotion, and the hosted API is China-jurisdiction, and self-hosting a 295B MoE still needs serious hardware. As an open-weight model, its running cost is your own hardware rather than a per-token fee.

The bottom line for this matchup

The defining split here is open vs. closed. Hunyuan Hy3 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. Claude Fable 5.1 gives you a managed, always-updated API with no infrastructure to run. Teams with GPUs, privacy requirements, or huge volume often favour the open model; teams that want zero ops and the latest capabilities favour the closed one. Capability is close enough that this operational question, not the benchmark, usually decides it.

Want both Claude Fable 5.1 and Hunyuan Hy3 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 5.1 or Hunyuan Hy3 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 5.1 leans toward terminal-bench-science agentic research (52.6%, more than double fable 5's 24.7%) while Hunyuan Hy3 leans toward frontier-level reported reasoning and science (gpqa diamond 90.4) at low active-parameter cost, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Fable 5.1 or Hunyuan Hy3?

Hunyuan Hy3 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while Claude Fable 5.1 is API-metered at $10/$50 per 1M tokens. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

Claude Fable 5.1 — 1M tokens vs 256K, about 3.9× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Claude Fable 5.1 and Hunyuan Hy3 together?

Yes — a multi-model platform like LumiChats gives you Claude Fable 5.1, Hunyuan Hy3 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 5.1 or Hunyuan Hy3?

Claude Fable 5.1 — released September 1, 2026, about 57 days after Hunyuan Hy3.

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.