Name: DeepSeek Reasoner
Author: DeepSeek

Question 1

What does this DeepSeek Reasoner vs DeepSeek V4 Flash comparison cover?

Accepted Answer

It brings together documented inputs and outputs, token limits, deployment terms and available pricing. When both models have source-linked, verified results on a shared benchmark, those results are shown with their individual sources. The comparison is a starting point for evaluating your own workload.

Question 2

Which is cheaper: DeepSeek Reasoner or DeepSeek V4 Flash?

Accepted Answer

DeepSeek Reasoner lists $0.14 input and $0.28 output per 1M tokens. DeepSeek V4 Flash lists $0.14 input and $0.28 output. The cheaper workload depends on the mix of input and output. Long-context tiers, caching, batch processing and retries can change the bill.

Question 3

Which has the larger context window: DeepSeek Reasoner or DeepSeek V4 Flash?

Accepted Answer

Both records list a 1M-token context window. An equal limit does not imply equal recall, instruction following, or long-context quality.

Question 4

Which is faster: DeepSeek Reasoner or DeepSeek V4 Flash?

Accepted Answer

There is no matched speed measurement for both models with the same source, host, region and date. Test the same prompts at your expected concurrency and measure time to the first useful response as well as complete task time.

Question 5

What input and output types do DeepSeek Reasoner and DeepSeek V4 Flash support?

Accepted Answer

DeepSeek Reasoner records text input and text output. DeepSeek V4 Flash records text input and text output. “Not documented” means the current source record is incomplete; it does not prove that a modality is unsupported.

Question 6

Should I choose DeepSeek Reasoner or DeepSeek V4 Flash?

Accepted Answer

The recorded figures alone do not establish a clear choice. Test both on the same representative examples and judge the output against your acceptance criteria. Include tool failures, retries and the time to a completed task.

Specification	DeepSeek Reasoner	DeepSeek V4 Flash
Provider	DeepSeek	DeepSeek
Listed pricing route	DeepSeek	DeepSeek
Model family	deepseek-thinking	deepseek-flash
Accepted inputs	text	text
Produced outputs	text	text
Context window	1M	1M
Max output	384K	384K
Input price / 1M	$0.14	$0.14
Output price / 1M	$0.28	$0.28
Reasoning mode	Documented	Documented
Tool calling	Documented	Documented
Image input	Not documented	Not documented
Audio input	Not documented	Not documented
Structured output	Not documented	Documented
License	Open weights	Open weights

DeepSeek Reasoner vs DeepSeek V4 Flash

DeepSeek Reasoner

DeepSeek V4 Flash

Key differences

Pricing, limits and capabilities

Which model should you choose?

Documentation and model profiles

Questions people ask

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