DeepSeek V4 is not waiting for you to notice. The API docs already expose deepseek-v4-pro and deepseek-v4-flash with 1M context, flat USD pricing, and a hard retirement date for legacy aliases deepseek-chat and deepseek-reasoner: 2026-07-24 15:59 UTC. If your configs still say “chat” or “reasoner”, July 24 is an outage event, not a deprecation warning. What is harder to verify from primary docs right now is the viral “peak/off-peak 2× Beijing hours” story: the official pricing page lists single off-peak-style USD rates only. This dossier separates verified migration facts from recap noise.
What GA means for V4 (verified)
Same model IDs · legacy aliases retire 24 July 2026 · open weights under MIT
DeepSeek’s April 2026 preview announcement states V4 preview is live and open-sourced, with weights on Hugging Face and API model ids deepseek-v4-pro and deepseek-v4-flash. The first API call docs and pricing table use those ids today. Legacy names map to V4 Flash modes until cutoff, then stop working.
“deepseek-chat & deepseek-reasoner will be fully retired and inaccessible after Jul 24th, 2026, 15:59 (UTC Time). (Currently routing to deepseek-v4-flash non-thinking/thinking).” – DeepSeek API Docs – V4 Preview Release
“The model names deepseek-chat and deepseek-reasoner will be deprecated on 2026/07/24 15:59 UTC. For compatibility, they correspond to the non-thinking mode and thinking mode of deepseek-v4-flash, respectively.” – DeepSeek API Docs – Your First API Call
“This repository and the model weights are licensed under the [MIT License](LICENSE).” – DeepSeek-V4-Pro README (Hugging Face)
Merits of the argument. MIT-licensed weights plus stable API ids give you three exit ramps: hosted API, self-host, or hybrid. The alias deadline is the only date you must calendar today; everything else is optimisation.
Official API pricing (flat USD, July 2026 docs)
Per-million-token table · cache hit rates matter for agents
DeepSeek’s Models & Pricing page lists per-1M-token USD charges for both tiers. Both support 1M context and up to 384K max output in the published table. Thinking mode is toggled per request rather than via separate model names after migration.
| Billing item | deepseek-v4-flash | deepseek-v4-pro |
|---|---|---|
| Input (cache hit) / 1M | $0.0028 | $0.003625 |
| Input (cache miss) / 1M | $0.14 | $0.435 |
| Output / 1M | $0.28 | $0.87 |
| Context length | 1M | 1M |
| Concurrency limit (docs footnote) | 2500 | 500 |
“The prices listed below are in units of per 1M tokens. A token, the smallest unit of text that the model recognizes, can be a word, a number, or even a punctuation mark. We will bill based on the total number of input and output tokens by the model.” – DeepSeek API Docs – Models & Pricing
Merits of the argument. Flash is the default economic choice for high-volume chat, classification, and many agent loops; Pro is for harder reasoning when Flash max thinking still misses your bar. Cache-hit pricing at sub-cent per million input tokens rewards repeated system prompts if your harness enables DeepSeek context caching.
Peak pricing: what we could not verify on primary docs
Recap blogs claim Beijing peak windows · official rate card is flat
Multiple third-party July 2026 articles describe GA “peak/off-peak” billing with 2× multipliers during Beijing business hours (often cited as 09:00–12:00 and 14:00–18:00 UTC+8). As of fetches against api-docs.deepseek.com/quick_start/pricing (English and Chinese), those pages show a single USD rate column with no peak multiplier table. We do not quote peak-hour figures as verified facts in this dossier.
Merits of the argument. Operators should watch the DeepSeek platform billing UI and changelog for pricing-structure emails (recap sites mention 24-hour notice) rather than scheduling batch jobs around recap timezone math until DeepSeek publishes peak tables on the official docs domain.
Model ID migration matrix
Replace aliases before 24 July 2026 · map thinking mode explicitly
| Legacy id | Current routing (until cutoff) | Target id | Thinking |
|---|---|---|---|
deepseek-chat |
V4 Flash non-thinking | deepseek-v4-flash |
disabled / non-think |
deepseek-reasoner |
V4 Flash thinking | deepseek-v4-flash |
enabled (see thinking_mode guide) |
| (new hard tasks) | – | deepseek-v4-pro |
per workload eval |
Base URLs remain https://api.deepseek.com (OpenAI format) and https://api.deepseek.com/anthropic (Anthropic format) per first-call docs.
Failure cases
Migration and cost surprises
- Missed alias deadline. Production configs referencing retired ids fail hard after 15:59 UTC on 24 July 2026.
- Assuming reasoner → Pro. Legacy reasoner maps to V4 Flash thinking, not Pro; quality/cost profiles differ.
- Peak pricing hearsay. Capacity plans built on unverified 2× windows may be wrong if your account still bills flat rates.
- Pro concurrency 500. Burst agent fleets may hit rate limits faster on Pro than Flash (2500 in docs table).
Migration steps
Search-replace ids · re-benchmark thinking modes
- Grep infra for
deepseek-chatanddeepseek-reasoner(env vars, Helm values, CI secrets). - Switch to
deepseek-v4-flashordeepseek-v4-prowith explicit thinking flags. - Run parallel shadow traffic for 48 hours; compare pass rate and token usage.
- Enable context caching on stable system prompts where supported.
- Optional: download MIT weights from Hugging Face collection if self-host is in scope.
curl https://api.deepseek.com/chat/completions
-H "Content-Type: application/json"
-H "Authorization: Bearer ${DEEPSEEK_API_KEY}"
-d '{
"model": "deepseek-v4-pro",
"messages": [
{"role": "system", "content": "You are a helpful assistant."},
{"role": "user", "content": "Hello!"}
],
"thinking": {"type": "enabled"},
"reasoning_effort": "high",
"stream": false
}'When flat V4 pricing is actually fine
High-volume Flash loops and open-weight optionality
- Batch extraction, L1 support triage, and agent workers where Flash thinking suffices.
- Teams needing MIT weights for air-gapped or cost-cap self-host (accept GPU capex).
- Off-peak batch reprocessing if your contract later adds time-of-day multipliers (monitor official docs).
What to check right now
Operator checklist
- Inventory every reference to legacy DeepSeek model names; deadline 2026-07-24 15:59 UTC.
- Confirm current invoice line items against
api-docs.deepseek.com/quick_start/pricing. - Benchmark Flash max vs Pro on your top 20 agent tasks.
- Subscribe to DeepSeek API changelog / platform notices for pricing-structure changes.
- Document fallback vendor if Pro concurrency limits bite.
Sources and references
Primary links for every quotation and load-bearing number in this dossier. Verify before you reuse a figure elsewhere.
- DeepSeek API Docs – Models & Pricing – USD rates, context 1M, model ids, alias footnote
- DeepSeek API Docs – Your First API Call – base URLs, model list, deprecation date
- DeepSeek API Docs – V4 Preview Release – open weights, 1M context, Jul 24 retirement note
- DeepSeek-V4-Pro README – MIT license statement
nJoy 😉