Claude Sonnet 5 vs DeepSeek V4-Pro
Anthropic's Claude Sonnet 5 and DeepSeek's DeepSeek V4-Pro both target production language workloads, but they price and behave differently. Here is the side-by-side.
Pricing checked against provider documentation on . How we verify
The short answer
DeepSeek V4-Pro is the cheaper option — roughly 4.0x less on a blended workload, and it suits frontier-adjacent reasoning at open-weight prices. Claude Sonnet 5 justifies its premium when you need fast claude-quality reasoning at scale.
Anthropic • Claude 5
$2.00 / $10.00
/ 1M tokens (input / output)
The workhorse Claude tier: a full million tokens of context and adaptive thinking at $2/$10, which undercuts the previous Sonnet 4.6 generation by a third on input while raising the context ceiling fivefold. The default pick for latency-sensitive products that still want Claude's writing and tool-use behaviour.
DeepSeek • DeepSeek V4
$0.66 / $1.98
/ 1M tokens (input / output)
A 1.6T-parameter mixture-of-experts model with 49B active, released under MIT and callable through DeepSeek's own API with configurable reasoning effort. Since 16 August 2026 DeepSeek bills on a peak/off-peak schedule, so the hour you run a job changes the bill by exactly 2x — which makes it unusually well suited to scheduled batch work.
Input price
DeepSeek V4-Pro is 67% cheaper than Claude Sonnet 5 on input tokens.
Output price
DeepSeek V4-Pro is 80% cheaper than Claude Sonnet 5 on output tokens — usually the side that dominates the bill.
Monthly cost at three workload sizes
Standard (non-batch, non-cached) rates. Reasoning models will exceed these figures because thinking tokens bill as output.
| Workload | Claude Sonnet 5 | DeepSeek V4-Pro | Difference |
|---|---|---|---|
| Light — 1M in / 200K out | $4 | $1 | $3 |
| Moderate — 10M in / 2M out | $40 | $11 | $29 |
| Heavy — 100M in / 20M out | $400 | $106 | $294 |
Specification comparison
| Attribute | Claude Sonnet 5 | DeepSeek V4-Pro |
|---|---|---|
| Input (/ 1M tokens) | $2.00 | $0.66 |
| Output (/ 1M tokens) | $10.00 | $1.98 |
| Cached input | $0.20 | $0.02 |
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Max output | 128,000 tokens | 131,072 tokens |
| Native reasoning | Yes | Yes |
| Knowledge cutoff | 2026-01 | 2026-03 |
| Relative latency | low | medium |
| Open weights | No | MIT |
| API model ID | claude-sonnet-5 | deepseek-v4-pro |
| Status | stable | stable |
DeepSeek V4-Pro: Off-peak rate shown. Peak rates are exactly double ($1.32 input / $3.96 output) during 01:00–04:00 and 06:00–10:00 UTC, Monday to Friday. Cache hits cost roughly 3% of a cache miss.
Choose Claude Sonnet 5 if…
- Production chat and copilots
- Long-document analysis
- Tool-heavy agents needing fast turns
- Code review and PR automation
Choose DeepSeek V4-Pro if…
- Overnight batch reasoning jobs
- Self-hosted deployments needing MIT terms
- Cost-sensitive coding agents
- Chinese-language workloads
Frequently asked
Is Claude Sonnet 5 or DeepSeek V4-Pro cheaper?
DeepSeek V4-Pro is cheaper. On a blended 3:1 input-to-output workload it costs about 4.0x less than Claude Sonnet 5.
Which has the larger context window, Claude Sonnet 5 or DeepSeek V4-Pro?
Both accept up to 1M tokens, so context is not a differentiator here.
Should I use Claude Sonnet 5 or DeepSeek V4-Pro?
Pick Claude Sonnet 5 for fast claude-quality reasoning at scale. Pick DeepSeek V4-Pro for frontier-adjacent reasoning at open-weight prices. If cost dominates the decision, DeepSeek V4-Pro wins; if you need the capability ceiling, benchmark both on your own evals before committing.