Hunyuan Hy3 vs NVIDIA Nemotron 3 Ultra

Tencent · China  |  NVIDIA · US · Updated June 2026

Quick verdict

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. Pick NVIDIA Nemotron 3 Ultra for the most capable open-weight model from a us lab (artificial analysis intelligence index of about 48) or fast, efficient long-horizon agentic reasoning via a hybrid mamba-transformer design.

Hunyuan Hy3 (Tencent, China) and NVIDIA Nemotron 3 Ultra (NVIDIA, US) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. Hunyuan Hy3 is a 295B Apache-2.0 open MoE that reaches frontier reasoning quality while running at roughly 21B active-parameter cost. NVIDIA Nemotron 3 Ultra is nVIDIA's open-weight reasoning flagship (about 550B total, 55B active) — the most capable open model from a US lab, built for long-running agents. Their biggest split is context window, and the breakdown below shows exactly how that plays out for your workload.

Key differences at a glance

Side-by-side specs

SpecHunyuan Hy3NVIDIA Nemotron 3 Ultra
ProviderTencent (China) NVIDIA (US)
ReleasedJuly 6, 2026 June 4, 2026
Context window256K (~384 pages) 1M (~1,500 pages)
Price (in/out)Open weight (self-host / free) Open weight (self-host / free)
Open weight?Yes — self-hostable Yes — self-hostable
Modalitiestext, code text, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

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

Hunyuan Hy3

A core design strength of Hunyuan Hy3.

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

Hunyuan Hy3

A core design strength of Hunyuan Hy3.

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

Hunyuan Hy3

A core design strength of Hunyuan Hy3.

The most capable open-weight model from a US lab (Artificial Analysis Intelligence Index of about 48)

NVIDIA Nemotron 3 Ultra

A core design strength of NVIDIA Nemotron 3 Ultra.

Fast, efficient long-horizon agentic reasoning via a hybrid Mamba-Transformer design

NVIDIA Nemotron 3 Ultra

A core design strength of NVIDIA Nemotron 3 Ultra.

A fully open release — weights, training data, and recipes under a permissive license

NVIDIA Nemotron 3 Ultra

A core design strength of NVIDIA Nemotron 3 Ultra.

Largest single-prompt input

NVIDIA Nemotron 3 Ultra

Its 1M window is about 3.9× larger, fitting roughly 1,500 pages in one prompt.

Which should you pick?

Someone analysing very long documents or codebases

NVIDIA Nemotron 3 Ultra

Larger 1M window fits more in one prompt.

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

Hunyuan Hy3

It is specifically built for that.

Anyone whose priority is the most capable open-weight model from a us lab (artificial analysis intelligence index of about 48)

NVIDIA Nemotron 3 Ultra

That is its strongest area.

An enterprise with regional data-residency rules

NVIDIA Nemotron 3 Ultra or Hunyuan Hy3

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

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 are real: 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.

NVIDIA Nemotron 3 Ultra: where it fits

NVIDIA's open-weight reasoning flagship (about 550B total, 55B active) — the most capable open model from a US lab, built for long-running agents. Released June 4, 2026 by NVIDIA, it is built for the most capable open-weight model from a US lab (Artificial Analysis Intelligence Index of about 48), fast, efficient long-horizon agentic reasoning via a hybrid Mamba-Transformer design, a fully open release — weights, training data, and recipes under a permissive license, and strong coding for an open model (SWE-Bench Verified in the high 60s).

Its trade-offs: trails the best Chinese open models on overall intelligence, and a 550B mixture-of-experts is heavy to self-host, and the 1M context is rarely served in full. As an open-weight model, its running cost is your own hardware rather than a per-token fee.

The bottom line for this matchup

This is less "which is smarter" and more "which ecosystem fits." Hunyuan Hy3 (China) and NVIDIA Nemotron 3 Ultra (US) differ on pricing philosophy, data-residency, and tooling as much as on raw scores. The pragmatic move is to run one real task through both and judge the outputs against your own constraints — including where your data is allowed to be processed.

Want both Hunyuan Hy3 and NVIDIA Nemotron 3 Ultra 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 Hunyuan Hy3 or NVIDIA Nemotron 3 Ultra 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, Hunyuan Hy3 leans toward frontier-level reported reasoning and science (gpqa diamond 90.4) at low active-parameter cost while NVIDIA Nemotron 3 Ultra leans toward the most capable open-weight model from a us lab (artificial analysis intelligence index of about 48), and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Hunyuan Hy3 or NVIDIA Nemotron 3 Ultra?

They are priced almost identically, so cost will not decide between them.

Which has the bigger context window?

NVIDIA Nemotron 3 Ultra — 1M 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 Hunyuan Hy3 and NVIDIA Nemotron 3 Ultra together?

Yes — a multi-model platform like LumiChats gives you Hunyuan Hy3, NVIDIA Nemotron 3 Ultra 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, Hunyuan Hy3 or NVIDIA Nemotron 3 Ultra?

Hunyuan Hy3 — released July 6, 2026, about 32 days after NVIDIA Nemotron 3 Ultra.

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.