AI Model (LLM API) · decision tool

DeepSeek V4 Pro vs DeepSeek V4 Flash — for your app, not in general

DeepSeek V4 Pro or DeepSeek V4 Flash? Set your usage, budget and constraints; the verdict, monthly cost and risks update live from verified pricing.

Prices verified 2026-07-13 against official pricing pages · fit weights are our estimates (see methodology) · share the URL to share your configuration

As of Jul 2026, with 50M input tokens/month, 10 millions output tokens / month, a $50 budget for this slot, DeepSeek V4 Pro ranks first for these inputs at 90% fit and a StackSays-estimated $30.45/month (DeepSeek V4 Flash: 84% fit, $5.39/month). Fit weights are our estimates; prices trace to official pages. Change any input below and the verdict recomputes.

Your situation

The verdict updates as you move these.

Input tokens / month (millions)prompts + context + RAG chunks; a modest AI feature runs 10–100MOutput tokens / month (millions)completions; usually 5–20% of input volumeBudget for this slot ($/mo)what you'd accept paying for the AI model layerTeam size1 = solo; bundled platforms save glue time for small teams

Narrow pick — the runner-up is close

DeepSeek V4 Profit 90% · est $30.45/mo

Open-weights workhorse at a fraction of closed-model prices

vs DeepSeek V4 Flash: fit 90% against 84%, est $30.45 against $5.39 per month

DeepSeek V4 Profit 90%

$30.45/mo

DeepSeek V4 Flashfit 84%

$5.39/mo

Comparing 2 tools head-to-head. Open the full field (10 options) →

The decision, in plain words

For a solo builder at 50M input tokens/month and a $50.00/mo budget for the AI model slot, DeepSeek V4 Pro leads at 90% fit and $30.45/mo. The two rules doing the work: budget fit (~$30.45/mo is 61% of your $50/mo budget); ecosystem maturity (established — our estimate from ecosystem age, docs and hiring pool).

DeepSeek V4 Flash runs close (84% fit, $5.39/mo). It takes the lead if ~$5.39/mo is 11% of your $50/mo budget matters more to you than the current weights assume.

Generated from the calculation above — every number traces to the sourced data; nothing here is written by an AI making things up.

Why DeepSeek V4 Pro scores 90%

Budget fit (weight 30, our estimate) — ~$30.45/mo is 61% of your $50/mo budget+26.73

Exit cost (weight 4, our estimate) — Open weights — self-host or switch inference providers freely+4

Ecosystem maturity (weight 8, our estimate) — established — our estimate from ecosystem age, docs and hiring pool+8

Capability tier (weight 14, our estimate) — workhorse — our estimate from vendor positioning, not a benchmark; budget models degrade first on long agentic chains+6.3

Total (lines sum exactly)45.03

Possible range −56…+56 (sum of active rule weights) · fit % = (total + max) / (2 × max)(45.03 + 56) / 112 = 90%

How the $30.45/mo estimate is calculated

input tokens overage — 50M over 0M included × $0.435/M$21.75

output tokens overage — 10M over 0M included × $0.87/M$8.70

Note — Prompt caching available (cached reads $0.0036/M) — not modeled here$0

Monthly total (lines sum exactly)$30.45

What could change this verdict

Cost risk

Estimated now (StackSays estimate, not your final bill)$30.45/mo · API pay-as-you-go

Free-tier statusNo free tier — paid from the first unit

Biggest unpriced/uncertain variablePrompt caching available (cached reads $0.0036/M) — not modeled here

Official prices verified 2026-07-13; calculation is deterministic code over those prices.

At a glance

Tool	Free tier	Paid entry	Verified
DeepSeek V4 Pro	No free tier	Pay-as-you-go — Prompt caching available (cached reads $0.0036/M) — not modeled here	2026-07-13
DeepSeek V4 Flash	No free tier	Pay-as-you-go — Prompt caching available (cached reads $0.0154/M) — not modeled here	2026-07-13

Where did you land?anonymous, one click

Data sources

Tool	Source	Verified
DeepSeek V4 Pro	OpenRouter live pricing (CalcSays daily sync, fetched 2026-07-13)	2026-07-13
DeepSeek V4 Flash	OpenRouter live pricing (CalcSays daily sync, fetched 2026-07-13)	2026-07-13

A monitor re-checks these pages for changes; when a vendor moves a price, the date updates and every verdict recomputes.

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