Which is cheaper, Claude Sonnet 5 or DeepSeek-V4-Flash?

DeepSeek-V4-Flash. On a task of 1,500 input and 500 output tokens across 3 calls, DeepSeek-V4-Flash costs $0.00396 per task against $0.02400 for Claude Sonnet 5, which makes it 6.06x cheaper (a 84% saving).

How much do Claude Sonnet 5 and DeepSeek-V4-Flash charge per million tokens?

Claude Sonnet 5: $2 per million input tokens and $10 per million output tokens. DeepSeek-V4-Flash: $0.44 input and $1.32 output. These are published list rates as of August 2026, excluding cached, batch and long-context tiers.

What does a million tasks cost on Claude Sonnet 5 vs DeepSeek-V4-Flash?

At the same fixed profile, one million tasks cost $24,000 on Claude Sonnet 5 and $3,960 on DeepSeek-V4-Flash. The gap comes entirely from list-price differences, not from any difference in the work done.

Model price comparisons · August 2026

Claude Sonnet 5 vs DeepSeek-V4-Flash: API pricing compared

Same task, same tokens, two invoices. Every figure on this page is computed from our open pricing dataset, not copied from a blog post.

DeepSeek-V4-Flash is 6.06x cheaper than Claude Sonnet 5 on a realistic task profile of 1,500 input and 500 output tokens per call, 3 calls per task: $0.00396 against $0.02400 per task, a 84% saving on identical work. Run a million tasks a month and that is the difference between $3,960 and $24,000.

Model	Input $/1M tok	Output $/1M tok	Output multiple	$/task	$/1M tasks
Claude Sonnet 5Anthropic · mid	$2	$10	5x	$0.02400	$24,000
DeepSeek-V4-FlashDeepSeek · value	$0.44	$1.32	3x	$0.00396	$3,960

Monthly bill at three volumes

Tasks / month	Claude Sonnet 5	DeepSeek-V4-Flash	Gap
10,000	$240	$40	$200
100,000	$2,400	$396	$2,004
1,000,000	$24,000	$3,960	$20,040

Where the money goes on each

Claude Sonnet 5 prices output at 5x its input rate, so on this profile output is 63% of its task cost. DeepSeek-V4-Flash prices output at 3x input, putting output at 50% of cost. The model with the higher output multiple rewards capping response length more; the one with the higher input share rewards prompt caching and context trimming more. Cost tells you nothing about quality: run both on twenty of your real cases before deciding, and treat the cheaper model as the default until it demonstrably fails.

Break-even against a dedicated GPU

Against a $2/hour dedicated instance ($1,460/month fixed), self-hosting overtakes Claude Sonnet 5 at 60,833 tasks per month and overtakes DeepSeek-V4-Flash at 368,687 tasks per month. The full method is in the self-hosting break-even guide.

Pricing the self-hosted side? Compare on-demand GPU rates:

Compare GPU cloud pricing →

Plug your own token counts into the $/task calculator, or read the full ten-model pricing comparison.

Compare against other models

Frequently asked

Which is cheaper, Claude Sonnet 5 or DeepSeek-V4-Flash?: DeepSeek-V4-Flash. On a task of 1,500 input and 500 output tokens across 3 calls, DeepSeek-V4-Flash costs $0.00396 per task against $0.02400 for Claude Sonnet 5, which makes it 6.06x cheaper (a 84% saving).
How much do Claude Sonnet 5 and DeepSeek-V4-Flash charge per million tokens?: Claude Sonnet 5: $2 per million input tokens and $10 per million output tokens. DeepSeek-V4-Flash: $0.44 input and $1.32 output. These are published list rates as of August 2026, excluding cached, batch and long-context tiers.
What does a million tasks cost on Claude Sonnet 5 vs DeepSeek-V4-Flash?: At the same fixed profile, one million tasks cost $24,000 on Claude Sonnet 5 and $3,960 on DeepSeek-V4-Flash. The gap comes entirely from list-price differences, not from any difference in the work done.