Preview to Official: What Changes in July

April 24 was the preview. Mid-July is the real launch. Two months of production usage, now graduating to stable.

Apr 24

Preview shipped

V4-Pro and V4-Flash released as preview under MIT license. Open weights, 1M context, production-ready API.

Jul ~15

Official launch

Stable V4 version with functional enhancements and performance gains. Peak-valley pricing activates.

Jul 24

Legacy retired

deepseek-chat and deepseek-reasoner endpoints fully retired at 15:59 UTC. No extensions.

Since April 24, V4-Pro and V4-Flash have been live in preview: stable enough for production, but labeled preview. DeepSeek confirmed on June 29, 2026 that the official V4 version ships in mid-July. This is not a point release. The official version brings functional enhancements, performance gains, and a new pricing model that changes the economics of peak-hour API usage.

If you are still on deepseek-chat or deepseek-reasoner, you have 24 days to migrate. The legacy endpoints will not survive July 24.


Peak-Valley Pricing: 2x During Business Hours

DeepSeek is introducing time-of-day pricing. Peak hours cost double. Off-peak stays the same.

ModelOff-Peak InputOff-Peak OutputPeak InputPeak Output
DeepSeek V4-Flash$0.14$0.28$0.28$0.56
DeepSeek V4-Pro$0.435$0.87$0.87$1.74
Claude Opus 4.7$5.00$25.00$5.00$25.00
GPT-5.5$5.00$30.00$5.00$30.00

Peak hours: 9am-12pm and 2pm-6pm daily. Even at peak pricing, V4-Flash output is 44-53x cheaper than GPT-5.5.

Cost comparison at peak vs off-peak

Even at double price, DeepSeek V4 remains dramatically cheaper than closed alternatives. The peak-valley mechanism is about load management, not margin extraction.

DeepSeek says the peak-valley mechanism is designed to optimize resource allocation and enhance service stability. During peak hours (9am-12pm, 2pm-6pm daily), API prices double. Off-peak rates remain at current levels. Even at peak pricing, V4-Flash output ($0.56/M) is 53x cheaper than GPT-5.5 ($30/M).

The strategic implication: batch processing, async workloads, and overnight inference jobs can run at the current rate. Real-time interactive usage during business hours absorbs the premium. This is load management, not price gouging.


DSpark: 85% Faster Generation, Now Live

DeepSeek and Peking University shipped an inference acceleration framework. Single-user generation speeds jumped 57-85%.

V4-Flash

60-85% faster

DSpark deployment boosts single-user generation speeds for V4-Flash by 60% to 85%. Validated in live production services.

V4-Pro

57-78% faster

V4-Pro sees 57-78% speed improvements. DeepSpec speculative decoding toolchain open-sourced alongside DSpark.

On June 27, DeepSeek collaborated with Peking University to release DSpark, an inference acceleration framework, and simultaneously open-sourced DeepSpec, a full-stack speculative decoding toolchain. The research paper, authored by DeepSeek founder Liang Wenfeng, has been uploaded to public code repositories.

This is DeepSeek first major open-source technical release following its $69 billion funding round. The benchmarks are not theoretical: DSpark has been fully deployed across online services and validated in production.

DSpark means the July launch ships faster than the preview. The inference speed improvement is not incremental. It changes the real-time interaction quality for both models.


Full Model Specifications

Everything confirmed from official sources, Hugging Face model cards, and the technical report.

SpecificationV4-ProV4-Flash
Total Parameters1.6 Trillion284 Billion
Active Parameters / Token49 Billion13 Billion
Pre-training Tokens33 Trillion+
Context Window1,000,000 tokens (default)
Max Output384,000 tokens
ArchitectureMixture-of-Experts (MoE), 1 shared + 256 routed experts, top-k=8
AttentionHybrid: CSA + HCA (DeepSeek Sparse Attention)
LicenseMIT (open weights, commercial use, fine-tuning allowed)
Reasoning ModesNon-think, Think High, Think Max
API CompatibilityOpenAI ChatCompletions + Anthropic API formats

Official specifications from DeepSeek API docs and Hugging Face model cards.

The key differentiator: V4 is the first model family built from the ground up around million-token contexts as a default, not a bolt-on feature.


What Makes V4 Different Under the Hood

Three innovations that make million-token context economically viable at production scale.

01

Hybrid Attention: CSA + HCA Vanilla attention has quadratic complexity. At 1M tokens, this becomes prohibitive. DeepSeek interleaves two mechanisms: Compressed Sparse Attention (CSA) compresses KV entries by 4x, then a lightning indexer picks only the top-k blocks. Heavily Compressed Attention (HCA) compresses by 128x and runs dense attention over the compressed sequence. The layers alternate. The result: V4-Pro requires only 27% of single-token inference FLOPs and 10% of KV cache compared to V3.2. V4-Flash pushes this to 10% of FLOPs and 7% of KV cache.

02

Manifold-Constrained Hyper-Connections (mHC) Conventional residual connections add a block delta to the running representation. With two attention variants competing for the residual stream, signals can drift. mHC replaces simple addition with a manifold constraint, projecting the residual mapping matrix onto the Birkhoff polytope via Sinkhorn-Knopp iteration. This bounds the spectral norm, keeping signal propagation stable across deep stacks. The practical impact: mHC enables reliable training at 1.6 trillion parameters. DeepSeek is the only lab that has solved the training stability issues and is shipping this in production.

03

Muon Optimizer + FP4 QAT at Frontier Scale DeepSeek replaced AdamW with the Muon optimizer for V4 training. Muon delivers faster convergence and greater training stability at trillion-parameter scale. MoE expert parameters use FP4 precision; most other parameters use FP8. This is the first FP4 quantization-aware training at frontier scale. Both models were pre-trained on more than 32 trillion tokens.

27%

FLOPs saved

V4-Pro at 1M tokens requires only 27% of single-token inference FLOPs compared to V3.2.

93%

KV cache saved

V4-Flash uses 7% of the KV cache that V3.2 would require at 1M tokens.

32T

tokens trained

Both models pre-trained on more than 32 trillion diverse, high-quality tokens.


How V4 Stacks Up Against the Frontier

Preview benchmarks are strong. The official version should close further gaps. Here is the current picture.

BenchmarkV4-Pro MaxClaude Opus 4.7GPT-5.5Gemini 3.1 Pro
SWE-bench Verified80.6%87.6%76.4%80.6%
SWE-bench Pro55.4%64.3%58.6%54.2%
LiveCodeBench93.588.891.291.7
Codeforces Rating320631683052
GPQA Diamond90.194.293.694.3
MATH-50096.1%94.5%93.4%
Terminal-Bench 2.067.9%69.4%82.7%68.5%
Putnam-2025120/120
MRCR 1M83.592.976.3

Benchmark scores from first-party reports and independent evaluations. V4-Pro Max mode shown for reasoning tasks.

V4 leads on competitive programming and math. Claude leads on real-world coding. GPT-5.5 leads on agentic tasks. No single model dominates.


Mathematical Reasoning: Where V4 Dominates

Formal math is one place V4 clearly stretches past the field. Perfect scores where competitors fall short.

Putnam-2025

120/120

Proof-perfect score, tying Axiom and ahead of Aristotle (100/120) and Seed-1.5-Prover (110/120). V4 reaches a perfect score on the hardest formal math benchmark.

Putnam-200 Pass@8

81.0

Compared to 35.5 for Seed-2.0-Pro, 26.5 for Gemini-3-Pro, and 26.5 for Seed-1.5-Prover. A 2.3x lead over the next competitor.

HMMT 2026 Feb

95.2

Within range of GPT-5.4 (97.7) and ahead of Gemini 3.1 Pro. Competition math at near-frontier level.

IMOAnswerBench

89.8

Ahead of Gemini 3.1 Pro and approaching GPT-5.4 (91.4). International math olympiad level reasoning.

For math-heavy workloads, V4-Pro at 1/9th the cost of GPT-5.5 delivers comparable results. The Putnam perfect score is a signal that formal reasoning capability has reached a new tier.


1 Million Tokens: The Default, Not a Feature

Both models support 1M-token context natively. No special tier. No price premium. This is the default.

Long-Context BenchmarkV4-ProClaude Opus 4.6Gemini 3.1 Pro
MRCR 1M (retrieval accuracy)83.592.976.3
CorpusQA 1M (real doc QA)62.0%71.7%53.8%
MRCR 128K94%96%89%

At 1M tokens, V4-Pro holds 94% retrieval accuracy up to 128K tokens and 82% at 512K tokens, still landing at 66% at 1M tokens. DeepSeek reports V4-Pro outperforms Gemini-3.1-Pro on the MRCR task (83.5 vs 76.3) but remains behind Claude Opus 4.6 (92.9).

On CorpusQA, a benchmark closer to real long-document use, V4-Pro reaches 62.0% at 1M tokens, beating Gemini 3.1 Pro at 53.8%. For long document QA, V4-Pro is genuinely competitive with the closed long-context leaders.

The practical impact: loading a full codebase at 1M tokens costs $0.14 per call on Flash. This is not a marginal difference. It changes what you can build.


Agentic Capabilities: The New Frontier

V4-Pro is integrated with Claude Code, OpenClaw, and OpenCode. The model was built for agent workflows.

Agentic BenchmarkV4-Pro MaxV4-Flash MaxClaude Opus 4.7
SWE-Bench Verified80.6%72.3%87.6%
SWE-Bench Pro55.4%42.1%64.3%
Terminal Bench 2.067.9%56.9%69.4%
MCPAtlas73.661.273.8
Toolathlon51.843.747.0

The MCPAtlas and Toolathlon numbers matter because those benchmarks evaluate a wide range of external tools and MCP services. A strong score indicates the model generalizes beyond whatever internal agent harness DeepSeek used during RL.

For agent use, Pro is the right model. For chat and reasoning workloads, Flash is close enough to Pro that the price-performance trade often favors it. V4-Flash-Max drops to 56.9% on Terminal Bench 2.0, 11 points behind Pro.


Top X Posts, Reddit Threads, and Community Buzz

The AI community reacted across X, Reddit, HuggingFace, and Hacker News. Three themes dominated.

X / Twitter

Official announcement went viral

DeepSeek official tweet: "DeepSeek-V4 Preview is officially live & open-sourced! Welcome to the era of cost-effective 1M context length." V4-Pro: 1.6T total / 49B active params. V4-Flash: 284B total / 13B active. Thousands of retweets and quote tweets.

r/LocalLLaMA

Architecture deep-dive

Top thread: "Takeaways & discussion about the DeepSeek V4 architecture" — analyzing CSA+HCA hybrid attention, mHC replacing residuals, and FP4 QAT at frontier scale. Community praised the architecture innovations over pure benchmark chasing.

r/DeepSeek

IDE and tooling discussions

Multiple threads on which IDEs work best with V4 Pro, Claude Code integration, and OpenCode compatibility. The Anthropic API format support made V4 a drop-in for existing Claude workflows.

r/SillyTavernAI

Flash vs Pro in practice

Community discussion: "DeepSeek V4 Flash vs Pro: any real differences in practice?" Consensus: Flash covers most real-world use cases. Pro is worth it for deep reasoning and complex coding tasks.

Hacker News

The weights were the story

HN noticed the launch link pointed to updated API docs, not a glossy launch page. The real payload was 865 GB of weights on Hugging Face. The story was that DeepSeek shipped something operationally real rather than just marketing.

HuggingFace

Massive downloads and debate

V4-Pro reached 123,000+ downloads within days. Community split between "I am so shocked" and "I am very disappointed." Critics flagged no native multimodality and Flash being too big for consumer hardware.

NVIDIA Forums

1M context on DGX Spark

The "Aiden Recipe" thread: community member deployed V4-Flash at full 1M context across two DGX Spark nodes. 30-45 tok/s decode, zero fabric delays, 89/100 tool-calling. Quad Spark setups emerging.

Cost savings

The 99% cost reduction stories

"I cut my AI API costs 99% by switching from Claude to DeepSeek" — real practitioner outcomes shared across forums. "DeepSeek V4 Pro at 5% the cost of Claude" framed as a structural cost advantage.

The community response was not just commentary. It was adoption. V4-Pro reached 123,000+ downloads on Hugging Face within days. The NVIDIA DGX Spark community built production-viable 1M context deployments. The cost reduction stories are real, not theoretical.


Top News Articles and Coverage

Every major AI publication covered V4. The coverage focused on three angles: price disruption, open-weight implications, and geopolitical risk.

Heise Online

AI Model DeepSeek v4

"AI Model DeepSeek v4: New Generation with 1.6 Trillion Parameters" — German tech publication highlighted the architecture innovations, pricing potential, and noted Bloomberg reports of a capacity bottleneck for the Pro model. New Huawei Ascend 950 clusters expected in H2 2026.

Lambda AI Blog

The most expected open-source model

"DeepSeek V4: the most expected open-source model ever released, and the quietest landing" — Lambda noted V4 architecture traces back through most of today strongest open-weight models. If 10x cheaper inference holds in production, the economics change.

DataCamp

Features, Benchmarks, and Comparisons

"DeepSeek V4: Features, Benchmarks, and Comparisons" — Comprehensive breakdown of V4 Pro vs Flash, API pricing, and head-to-head against GPT-5.5 and Opus 4.7. Called out the 7-9x cost reduction as a paradigm shift.

Macrostream

Peak-Valley API Pricing

"DeepSeek V4 Set for Mid-July Launch as Peak-Valley API Pricing Takes Effect" — Broke the July launch timeline and peak-valley pricing details. DSpark inference acceleration framework fully deployed.

BenchLM

The Frontier in April 2026

"DeepSeek V4 Pro vs Claude Opus 4.7 vs GPT-5.5: The Frontier in April 2026" — Three frontier flagships in eight days. V4-Pro undercuts GPT-5.5 by ~9x on output price under MIT license.

DEV Community

What is Inside, How It Compares

"DeepSeek V4: What is Inside, How It Compares, and Where It Actually Wins" — Practical assessment from engineering perspective. Price is not the complete picture; V4 performs well on some workloads and poorly on others.

The coverage pattern is consistent: V4 wins on price and competitive programming, trails on real-world software engineering and agentic tasks, and the open-weight MIT license changes the self-hosting calculus entirely.


The July 24 Deadline: Legacy API Retirement

If you use deepseek-chat or deepseek-reasoner, you have 24 days to migrate. After July 24, these endpoints fail.

Hard deadline

July 24, 2026 at 15:59 UTC

After this moment, requests using deepseek-chat or deepseek-reasoner fail. DeepSeek official change log states both names will be fully retired and inaccessible. No announced extension.

Migration path

Switch to deepseek-v4-pro or deepseek-v4-flash

Until the deadline, legacy aliases transparently route to V4-Flash. The API is compatible. Change the model parameter to migrate.

The migration is straightforward: change your model parameter from deepseek-chat to deepseek-v4-flash, or from deepseek-reasoner to deepseek-v4-pro. The API base URL stays the same. Both OpenAI ChatCompletions and Anthropic API formats are supported.

DeepSeek recommends migrating and re-testing now rather than waiting until July. Preview-stage behavior can shift. The July 24 deadline is firm.


The Safety and Geopolitical Layer

Government restrictions, data residency concerns, distillation allegations, and the self-hosting angle.

Government restrictions

Multiple countries have restricted DeepSeek

Italy banned DeepSeek from app stores within 72 hours. Australia, Taiwan, South Korea, the US Navy, and NASA have restricted it. Several US states have restricted use on government devices.

Data residency

Data governed by PRC law

DeepSeek privacy policy states user data is stored in PRC servers and governed by PRC law. China National Intelligence Law Article 7 requires all organizations to support national intelligence work.

Distillation

Unresolved allegations

The White House accused Chinese actors including DeepSeek of industrial-scale distillation campaigns. Anthropic and OpenAI alleged over 24,000 fake accounts and 16 million interactions. DeepSeek has not publicly addressed these.

Self-hosting angle

MIT license changes the calculus

MIT license allows full commercial use, modification, and redistribution. For GDPR compliance, self-hosting on EU-based servers means data never reaches China. The open-weight model, self-hosted, is a different product than the hosted API.

The question is not whether the hosted API is safe for regulated data. It is not. The question is whether the open-weight model, self-hosted, changes the calculus. For many use cases, it does.


The Complete Pricing Picture

Off-peak, peak, cache-hit, and self-hosted costs. The full economic breakdown.

ModelInput /MTokOutput /MTokCache-Hit InputContext
V4-Flash (off-peak)$0.14$0.28$0.00281M
V4-Flash (peak)$0.28$0.56$0.00561M
V4-Pro (off-peak)$0.435$0.87$0.00361M
V4-Pro (peak)$0.87$1.74$0.00721M
Claude Opus 4.7$5.00$25.00$0.501M
GPT-5.5$5.00$30.00$0.501M

Complete pricing as of July 2026. Peak hours: 9am-12pm, 2pm-6pm daily. Cache-hit pricing offers 98% reduction from cache-miss.

For a real-world workload: processing 10 million output tokens costs $2.80 with V4-Flash off-peak, $5.60 at peak, $34.80 with V4-Pro off-peak, $250 with Claude Opus 4.7, and $300 with GPT-5.5.

Cache-hit pricing is where V4 pulls even further ahead. V4-Flash cache-hit input is $0.0028 per million tokens, a 98% reduction from cache-miss. For repetitive workloads with similar prompts, the effective cost approaches zero.


The Real Comparison: Which Model for Which Task

Stop looking at the leaderboard. Look at the task matrix. Different models for different workloads.

Use CaseBest ModelWhy
High-volume production API callsDeepSeek V4-Flash$0.14/$0.28 per M tokens off-peak, 97-107x cheaper than GPT-5.5
Budget frontier qualityDeepSeek V4-Pro80.6% SWE-Bench at 11x lower cost than Opus
Competitive programmingDeepSeek V4-ProCodeforces 3206, highest ever AI rating
Math and STEM reasoningDeepSeek V4-ProMATH-500 at 96.1%, Putnam-2025 at 120/120
Self-hosting or air-gapped deploymentDeepSeek V4-ProMIT-licensed open weights, 865 GB
Fine-tuning on proprietary dataDeepSeek V4-ProOpen weights allow full fine-tuning, commercial use
Terminal-heavy agentic codingGPT-5.582.7% on Terminal-Bench 2.0
Critical PR review and refactorClaude Opus 4.787.6% SWE-bench Verified, strongest self-verification
Long autonomous + computer useGPT-5.5Native computer use, 7+ hour autonomous task horizon
Broadest agent ecosystemGPT-5.5Widest tool-calling support, de facto standard

The Multi-Model Strategy

The most sophisticated builders are building a routing layer. Different models for different tasks.

60-70%

DeepSeek V4-Flash

$0.14/$0.28 per M tokens. Classification, extraction, routing, high-volume tasks. The cheap workhorse that handles the bulk.

20-25%

DeepSeek V4-Pro

$0.435/$0.87 per M tokens. Standard coding, reasoning, long-document processing. Budget frontier quality.

5-10%

Claude Opus 4.7

$5/$25 per M tokens. High-stakes refactoring, critical review, when quality matters more than cost. The safety net.

5-10%

GPT-5.5

$5/$30 per M tokens. Multi-hour agentic workflows, computer use, autonomous execution. The deep work engine.

A well-designed routing layer that sends 60-70% of traffic to V4-Flash, escalates coding to V4-Pro or Opus 4.7, and uses GPT-5.5 for agentic desktop tasks can reduce costs 40-60% compared to a single-model approach while maintaining or improving quality across all task types.

Most calls are routine. Some calls need frontier quality. A few calls need autonomous depth. Optimize for the actual distribution of tasks in production.


What the Official V4 Launch Should Bring

Based on DeepSeek statements and the preview-to-stable pattern, here is what changes in mid-July.

Performance improvements

DeepSeek confirmed the official version delivers "further functional enhancements and performance gains." The preview was already competitive with frontier models.

Peak-valley pricing activates

Time-of-day pricing kicks in. Batch and async workloads benefit from off-peak rates. Real-time usage during business hours absorbs the premium.

DSpark inference acceleration

The 60-85% speed boost from DSpark should be fully integrated. Single-user generation speeds improve dramatically for both models.

Legacy API retirement

deepseek-chat and deepseek-reasoner fully retired July 24. The official launch clears the path for a clean V4-only API.

Possible multimodal hints

Vision capabilities have appeared in test interfaces but remain unverified. DeepSeek has not confirmed multimodal support for the official launch.

Huawei Ascend 950 capacity

Bloomberg reports a capacity bottleneck for the Pro model. New Huawei Ascend 950 clusters expected in H2 2026, which should alleviate shortages and potentially lower prices.


Sources

Every claim on this page ties back to a first-party or verified source. No invented numbers.

Last updated July 29, 2026. Pricing from official DeepSeek API documentation. Benchmark scores from first-party reports and independent evaluations. Community discussions sourced from Reddit, X, HN, and HuggingFace.


The preview was good. The official version should be better.

DeepSeek V4 already rewrote the economics of AI in April. The July official launch makes it permanent. If you are still paying $25-30 per million output tokens for tasks that V4 handles at $0.28-0.87, the question is not whether to switch. It is how fast you can migrate.

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