Pricing comparison

Gemini 3.5 Flash vs DeepSeek V4 Pro

Per-token pricing, full-workload cost ladders, and monthly volume projections. Numbers sourced directly from each provider's rate card.

Google

Gemini 3.5 Flash

Input
$1.50 / 1M
Output
$9.00 / 1M
Cached input
-
Context
1M
Max output
66K

DeepSeek

DeepSeek V4 Pro

Input
$1.74 / 1M
Output
$3.48 / 1M
Cached input
-
Context
1M
Max output
384K

Cost per request

Four common workload shapes, input tokens and a 1:2 output ratio (a standard chat/completion pattern). Long-context surcharges apply automatically where the provider charges them.

ScenarioTokens (in / out)Gemini 3.5 FlashDeepSeek V4 ProWinner
Short prompt100 / 200$0.0020$0.0009DeepSeek V4 Pro
Typical request1,000 / 2,000$0.0195$0.0087DeepSeek V4 Pro
Long document10,000 / 5,000$0.0600$0.0348DeepSeek V4 Pro
Large prompt100,000 / 10,000$0.2400$0.2088DeepSeek V4 Pro

Monthly bill at scale

Projected monthly cost at typical request volume, assuming the "typical request" shape above (1k in, 2k out).

TrafficReq / monthGemini 3.5 FlashDeepSeek V4 ProDelta
Small SaaS1,000$19.50$8.70DeepSeek V4 Pro -$10.80
Growing product10,000$195.00$87.00DeepSeek V4 Pro -$108.00
Heavy usage100,000$1,950$870.00DeepSeek V4 Pro -$1,080

Which should you use?

For the typical chat-shape request (~1k input, 2k output), DeepSeek V4 Pro comes out 124% cheaper. If you're picking one as the default, that's usually the right choice on cost alone.

Split decision: Gemini 3.5 Flash has the cheaper input rate, while DeepSeek V4 Pro has the cheaper output rate. RAG and long-context workloads favour the former; generation-heavy workloads (long responses, agentic loops) favour the latter.

Live cost calculator

Type in any token counts - both prices update instantly. Uses base input/output rates (no cache discount, no long-context tier).

Gemini 3.5 Flash

$0.0060

per request

DeepSeek V4 Pro

$0.0035

per request

DeepSeek V4 Pro is $0.0025 cheaper per request (42.0% less).

Try both in the estimator →

Drop your actual prompt in, tokens are counted with the provider's own tokenizer, and the dollar number matches what lands on your invoice.

Frequently asked

Which is cheaper, Gemini 3.5 Flash or DeepSeek V4 Pro?
On a typical 1,000-input / 2,000-output request, DeepSeek V4 Pro costs ~$0.0087 vs ~$0.0195 on Gemini 3.5 Flash. Input or output rates can flip the answer for very lopsided workloads - see the cost ladder above.
What's the difference in per-token pricing?
Gemini 3.5 Flash charges $1.50 per 1M input tokens and $9.00 per 1M output tokens. DeepSeek V4 Pro charges $1.74 / $3.48 per 1M.
Which has the bigger context window?
Both hold 1M of input.
How fresh is this comparison?
Gemini 3.5 Flash was re-verified on 2026-07-01 and DeepSeek V4 Pro on 2026-07-01 against each provider's published rate card. Calcis re-checks every row on a rolling schedule and re-deploys when a provider changes pricing.

Gemini 3.5 Flash verified 2026-07-01 · DeepSeek V4 Pro verified 2026-07-01. Rate cards at Google and DeepSeek.