Hunyuan Hy4 Preview vs Kimi K2.5

Tencent · China  |  Moonshot AI · China · Updated June 2026

Quick verdict

Pick Hunyuan Hy4 Preview for gpqa diamond (92.3) or terminal-bench (85.4). Pick Kimi K2.5 for native multimodal reasoning and visual coding or agentic tool-calling and self-directed multi-step work. On a tight budget at scale, Kimi K2.5 is the value pick.

Hunyuan Hy4 Preview (Tencent) and Kimi K2.5 (Moonshot AI) are two of the models people most often weigh against each other in 2026. Hunyuan Hy4 Preview is tencent's open-sourced (Apache 2.0) next-generation Hunyuan flagship preview, released August 28, 2026 as a 770B-parameter (49B active) MoE model that helped optimize its own training pipeline. Kimi K2.5 is moonshot's open-weight multimodal model at $0.60/$2.50 with a 256K window — strong visual coding and agentic work, since superseded by K2.6/K2.7. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecHunyuan Hy4 PreviewKimi K2.5
ProviderTencent (China) Moonshot AI (China)
ReleasedAugust 28, 2026 January 27, 2026
Context window1M+ tokens (~1,500 pages) 256K (~393 pages)
Price (in/out)$0.834/$2.501 per 1M tokens $0.45/$2.25 per 1M tokens
Open weight?Yes — self-hostable Yes — self-hostable
Modalitiestext text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

GPQA Diamond (92.3)

Hunyuan Hy4 Preview

Tencent's open-sourced (Apache 2.0) next-generation Hunyuan flagship preview, released August 28, 2026 as a 770B-parameter (49B active) MoE model that helped optimize its own training pipeline — and it carries the larger 1M+ tokens context.

Terminal-Bench (85.4)

Hunyuan Hy4 Preview

Kimi K2.5 is comparatively weak here — its coding score uses Moonshot's own harness, not the standard SWE-Bench Verified protocol

SWE-bench Multilingual (82.9)

Hunyuan Hy4 Preview

Tencent's open-sourced (Apache 2.0) next-generation Hunyuan flagship preview, released August 28, 2026 as a 770B-parameter (49B active) MoE model that helped optimize its own training pipeline — and it is the newer of the two.

Native multimodal reasoning and visual coding

Kimi K2.5

Hunyuan Hy4 Preview is comparatively weak here — text-only, no native vision support

Agentic tool-calling and self-directed multi-step work

Kimi K2.5

Moonshot's open-weight multimodal model at $0.60/$2.50 with a 256K window — strong visual coding and agentic work, since superseded by K2.6/K2.7 — and it runs cheaper at $0.45/$2.25 per 1M tokens.

Open-weight (Modified-MIT) — self-hostable at 256K context

Kimi K2.5

Kimi K2.5 lists open-weight (Modified-MIT) — self-hostable at 256K context among its strengths; Hunyuan Hy4 Preview does not.

Lowest cost at scale

Kimi K2.5

At $0.45/$2.25 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Hunyuan Hy4 Preview

Its 1M+ tokens window is about 3.8× larger than Kimi K2.5's 256K, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Kimi K2.5

At $0.45/$2.25 per 1M tokens it undercuts Hunyuan Hy4 Preview, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Hunyuan Hy4 Preview

Larger 1M+ tokens window fits more in one prompt.

Anyone whose priority is gpqa diamond (92.3)

Hunyuan Hy4 Preview

It is specifically built for that.

Anyone whose priority is native multimodal reasoning and visual coding

Kimi K2.5

That is its strongest area.

Hunyuan Hy4 Preview: where it fits

Tencent's open-sourced (Apache 2.0) next-generation Hunyuan flagship preview, released August 28, 2026 as a 770B-parameter (49B active) MoE model that helped optimize its own training pipeline. Released August 28, 2026 by Tencent, it is built for gPQA Diamond (92.3), terminal-Bench (85.4), sWE-bench Multilingual (82.9), and large jump in long-horizon coding vs prior Hunyuan model (DeepSWE 28.0 to 64.3).

Its trade-offs are real: text-only, no native vision support, labeled a 'preview', not yet Tencent's finalized GA flagship, and sWE-Marathon score still low in absolute terms (31.9) despite a large relative jump. At $0.834 in / $2.501 out per million tokens, it sits in the budget price band.

Kimi K2.5: where it fits

Moonshot's open-weight multimodal model at $0.60/$2.50 with a 256K window — strong visual coding and agentic work, since superseded by K2.6/K2.7. Released January 27, 2026 by Moonshot AI, it is built for native multimodal reasoning and visual coding, agentic tool-calling and self-directed multi-step work, open-weight (Modified-MIT) — self-hostable at 256K context, and vendor reports around 76.8% on its own SWE-agent coding harness.

Its trade-offs: its coding score uses Moonshot's own harness, not the standard SWE-Bench Verified protocol, superseded within Moonshot's line by Kimi K2.6 and K2.7, openRouter shows a promo price below Moonshot's $0.60/$2.50 list, and image input but no audio or video. At $0.45 in / $2.25 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

Hunyuan Hy4 Preview and Kimi K2.5 overlap enough that the right pick depends on your specific job. Kimi K2.5 costs less per token; Hunyuan Hy4 Preview holds the larger context; and each leads in its own area — Hunyuan Hy4 Preview for gpqa diamond (92.3), Kimi K2.5 for native multimodal reasoning and visual coding. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Hunyuan Hy4 Preview and Kimi K2.5 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 Hy4 Preview or Kimi K2.5 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, Hunyuan Hy4 Preview leans toward gpqa diamond (92.3) while Kimi K2.5 leans toward native multimodal reasoning and visual coding, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Hunyuan Hy4 Preview or Kimi K2.5?

Kimi K2.5 is cheaper — $0.834/$2.501 per 1M tokens vs $0.45/$2.25 per 1M tokens, roughly 1.9× apart on input.

Which has the bigger context window?

Hunyuan Hy4 Preview — 1M+ tokens vs 256K, about 3.8× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Hunyuan Hy4 Preview and Kimi K2.5 together?

Yes — a multi-model platform like LumiChats gives you Hunyuan Hy4 Preview, Kimi K2.5 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 Hy4 Preview or Kimi K2.5?

Hunyuan Hy4 Preview — released August 28, 2026, about 7 months after Kimi K2.5.

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.