Hy4 vs DeepSeek — Tencent Hy4 Preview vs DeepSeek V4 Pro

A side-by-side comparison of Tencent Hy4 Preview and DeepSeek-V4-Pro covering architecture, parameters, context window, pricing, output limits, and open-source status. Last updated: August 28, 2026.

Head-to-Head Specification Table

Hy4 PreviewDeepSeek-V4-ProDeepSeek-V4-Flash
DeveloperTencent Hy TeamDeepSeekDeepSeek
ArchitectureMoEMoE + DSA sparse attentionMoE
Total parameters770B1.6T284B
Active parameters / token49B49B13B
Activation ratio≈6.4%≈3.1%≈4.6%
Layers786161
Experts per MoE layer256 routed + 1 shared384 routed + 1 shared384 routed + 1 shared
Experts activated per tokentop-8 + sharedtop-6 + sharedtop-6 + shared
Max output64K384K384K
Input price (1M)$0.834 (flat)$0.66 off-peak / $1.32 peak$0.22 off-peak / $0.44 peak
Output price (1M)$2.501 (flat)$1.98 off-peak / $3.96 peak$0.66 off-peak / $1.32 peak
Open weightsNo (hosted API only)YesYes
Release2026 (grey-testing)2026-04-24 (GA 2026-08-13)2026-04-24

Sources: Tencent Hy official research page and HuggingFace; DeepSeek API Docs, Models & Pricing, and V4 Preview release notes. DeepSeek prices shown are cache-miss rates; cache-hit rates may be lower.

The Most Interesting Detail: Same 49B Active, Very Different Total

Both Hy4 Preview and DeepSeek-V4-Pro activate 49B parameters per token. Hy4 reaches that active count with 770B total parameters, while DeepSeek-V4-Pro lists 1.6T total. Their activation ratios are therefore different: approximately 6.4% for Hy4 and 3.1% for DeepSeek-V4-Pro.

In practical terms, a higher activation ratio can mean capacity is distributed across fewer, larger experts, while a lower ratio can reflect a larger pool of specialists with a smaller share selected for each token. Neither ratio is a universal quality score. Hy4 documents its internals in unusual detail—78 layers, 256 routed experts plus one shared expert per layer, top-8 routing, and a native MTP layer—while equivalent layer-level detail for DeepSeek is not listed here.

Architecture Compared

Hy4 Preview

This is a Mixture-of-Experts model with a 78-layer backbone. Layer 1 is a dense FFN; layers 2–78 each contain 256 routed experts and one shared expert. Every token activates the top eight routed experts plus the shared expert. A native MTP layer, listed as 10B total and 0.7B active parameters, supports speculative decoding when enabled by the provider.

DeepSeek-V4-Pro

This model lists 1.6T total parameters and 49B active per token. Its headline structural features include token-wise compression and DSA (DeepSeek Sparse Attention). DeepSeek describes these techniques as a way to improve long-context efficiency while reducing compute and memory requirements.

Takeaway: Hy4 provides more publicly listed expert-level architectural detail, while DeepSeek emphasizes sparse-attention and long-context efficiency engineering. They represent different routes toward a 1M-token context goal.

Pricing Compared (per 1M tokens)

ModelInputOutputPricing model
Hy4 Preview$0.834$2.501Flat rate
DeepSeek-V4-Pro$0.66 off-peak / $1.32 peak$1.98 / $3.96Peak / off-peak
DeepSeek-V4-Flash$0.22 / $0.44$0.66 / $1.32Peak / off-peak

On the listed cache-miss rates, DeepSeek is cheaper: V4-Pro off-peak input is $0.66 versus Hy4's $0.834, and V4-Flash is lower still. The comparison is not entirely direct because DeepSeek splits peak and off-peak pricing while Hy4 uses one flat rate. During DeepSeek peak hours, V4-Pro input rises to $1.32, above Hy4's listed rate. Cache-hit pricing can also materially change the effective cost.

Note: verify current prices and peak-hour definitions on the provider's official pricing page before deploying a production workload.

Output Limit and Open-Source Status

Maximum output is DeepSeek's clear advantage: 384K tokens versus Hy4's 64K. For workflows that generate very long artifacts, that larger ceiling provides more headroom, although applications should still set practical output limits.

Open weights are another major difference: the supplied comparison lists both V4-Pro and V4-Flash as available on HuggingFace. Hy4 Preview is currently a hosted API with model ID tencent/hy4-preview. If self-hosting or fine-tuning is a requirement, confirm the latest release and license status before choosing a service.

Bottom Line: Which Should You Choose?

Your situationRelevant option
Need open weights, self-hosting, or fine-tuningDeepSeek-V4-Pro / Flash
Need very long output above 64KDeepSeek-V4-Pro / Flash
Lowest listed cost per tokenDeepSeek-V4-Flash
Want Tencent ecosystem integration and flat pricingHy4 Preview
Want detailed expert architecture and native MTP documentationHy4 Preview

Hy4 Preview is still in grey-testing, so its positioning and pricing may change. DeepSeek V4 is listed as generally available. The right choice depends on whether your priority is open weights, output length, cost controls, ecosystem integration, or a hosted API workflow.

Get Hy4 API Access on TokenRa →

Frequently Asked Questions

Is Hy4 better than DeepSeek V4?

They target different strengths. Hy4 Preview has a more detailed expert architecture and a simpler flat pricing model, while DeepSeek-V4-Pro is open-sourced, supports a much larger maximum output, and is cheaper on input off-peak. Which is better depends on your workload and whether you need open weights.

How do Hy4 and DeepSeek V4 parameters compare?

Both activate 49B parameters per token. Hy4 Preview has 770B total parameters, while DeepSeek-V4-Pro has 1.6T total parameters. DeepSeek-V4-Flash is smaller at 284B total and 13B active.

Is Hy4 cheaper than DeepSeek?

No. Hy4 Preview is priced at $0.834 per 1M input and $2.501 per 1M output. DeepSeek-V4-Pro off-peak is $0.66 input and $1.98 output, while DeepSeek-V4-Flash is $0.22 input and $0.66 output. DeepSeek uses peak and off-peak pricing while Hy4 uses a single flat rate.

Is DeepSeek V4 open source?

Yes. DeepSeek-V4-Pro and V4-Flash are open-weight models available on HuggingFace. Hy4 Preview is currently served only as a hosted API with model ID tencent/hy4-preview and has not been open-sourced.