Claude Opus 5.5 vs DeepSeek V4 Pro — Price, Context, and Capability Compared
Claude Opus 5.5 vs DeepSeek V4 Pro: which should I use?
Claude Opus 5.5 costs 4.0× more per blended million tokens than DeepSeek V4 Pro. Claude Opus 5.5 has the larger context window (1,000,000 tokens). Default to DeepSeek V4 Pro unless you specifically need Claude Opus 5.5's edge.
Where can you find price, speed, and task evidence for Claude Opus 5.5 and DeepSeek V4 Pro?
Which tasks fit Claude Opus 5.5 and DeepSeek V4 Pro?
Best-fit task signals from the published model strengths; this is not a substitute for a controlled benchmark.
| Fact | Claude Opus 5.5 | DeepSeek V4 Pro |
|---|---|---|
| Best fit | The hardest reasoning, coding, and long-horizon agentic tasks. | Rigorous math, proofs, and hard algorithmic problems on a budget. |
| Reasoning mode | Available | Available |
What does a Coding Agent workload cost with Claude Opus 5.5 and DeepSeek V4 Pro?
Modeled for Coding Agent: 20,000 input + 2,000 output tokens per task, 1 turn. This is a workload model, not a provider quote.
| Fact | Claude Opus 5.5 | DeepSeek V4 Pro |
|---|---|---|
| Coding Agent / task | $0.12 (modeled) | $0.03 (modeled) (winner) |
| Input / output rate | $4.00 / $20.00 per M | $1.32 / $3.96 per M |
How fast are Claude Opus 5.5 and DeepSeek V4 Pro?
Only non-estimated benchmark results are shown as measured.
| Fact | Claude Opus 5.5 | DeepSeek V4 Pro |
|---|---|---|
| Measured throughput | Unavailable | 68 tokens/s |
| Time to first token | Unavailable | 480 ms |
How compatible are Claude Opus 5.5 and DeepSeek V4 Pro with APIs?
Provider-level wire-format and SDK facts; model-specific parameter differences may still apply.
| Fact | Claude Opus 5.5 | DeepSeek V4 Pro |
|---|---|---|
| OpenAI SDK | Not drop-in | Usable |
| Request shape | Messages API — system prompt is a top-level field, not a message role, and max_tokens is required on every call. | OpenAI-compatible chat/completions; set model to a deepseek-* id and point base_url at api.deepseek.com. |
| Streaming | SSE (Anthropic content-block events) | SSE (OpenAI delta) |
What are the privacy and retention policies for Claude Opus 5.5 and DeepSeek V4 Pro?
Provider policy and residency facts from the verified provider registry. A missing retention policy is not treated as a guarantee.
| Fact | Claude Opus 5.5 | DeepSeek V4 Pro |
|---|---|---|
| Provider says API data trains models | No | Unavailable |
| Published retention period | Unavailable | Unavailable |
| Data residency | Unavailable | Unavailable |
How much effort does it take to migrate between Claude Opus 5.5 and DeepSeek V4 Pro?
Direction is from each displayed model to the other. Effort is derived from provider compatibility and published parameter maps.
| Fact | Claude Opus 5.5 | DeepSeek V4 Pro |
|---|---|---|
| Move Claude Opus 5.5 → DeepSeek V4 Pro | config; 3 breaking parameter differences | Target: DeepSeek V4 Pro |
| Move DeepSeek V4 Pro → Claude Opus 5.5 | Source: DeepSeek V4 Pro | code-change; 3 breaking parameter differences |
| Why | Keep the `openai` SDK; change `baseURL` and the API key. | Messages API — system prompt is a top-level field, not a message role, and max_tokens is required on every call. |
How do Claude Opus 5.5 and DeepSeek V4 Pro compare on specs?
| Claude Opus 5.5 | DeepSeek V4 Pro | |
|---|---|---|
| Price (input) | $4.00/M | $1.32/M ✓ |
| Price (output) | $20.00/M | $3.96/M ✓ |
| Blended price | $8.00/M | $1.98/M ✓ |
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Max output | 128,000 tokens | 384,000 tokens ✓ |
| Modalities | text, vision | text |
| Reasoning mode | Yes | Yes |
| Released | 2026-09 | 2026-05 |
| Speed | Not measured | 68 t/s |
How much do Claude Opus 5.5 and DeepSeek V4 Pro cost at scale?
| Tokens / month | Claude Opus 5.5 | DeepSeek V4 Pro | Delta |
|---|---|---|---|
| 1,000,000 | $8.00 | $1.98 | $6.02 (4.0×) |
| 10,000,000 | $80.00 | $19.80 | $60.20 (4.0×) |
| 100,000,000 | $800.00 | $198.00 | $602.00 (4.0×) |
Choose Claude Opus 5.5 if…
- ✓Anthropic's strongest reasoning and coding
- ✓1M-token context
- ✓Extended-thinking mode for complex agentic work
- ✓The hardest reasoning, coding, and long-horizon agentic tasks.
Choose DeepSeek V4 Pro if…
- ✓Thinking mode with visible chain-of-thought
- ✓Frontier-level math and competition coding
- ✓Still far cheaper than closed frontier models
- ✓Rigorous math, proofs, and hard algorithmic problems on a budget.
Run this exact matchup right now
Send the same prompt to Claude Opus 5.5 and DeepSeek V4 Pro side by side and see the outputs yourself.
Try Claude Opus 5.5 vs DeepSeek V4 Pro FreeWhat are common questions about Claude Opus 5.5 and DeepSeek V4 Pro?
Is Claude Opus 5.5 cheaper than DeepSeek V4 Pro?
DeepSeek V4 Pro is cheaper, at $1.98 per million blended tokens vs $8.00 for Claude Opus 5.5.
Which has the bigger context window, Claude Opus 5.5 or DeepSeek V4 Pro?
Both models support 1,000,000 tokens of context.
Can Claude Opus 5.5 replace DeepSeek V4 Pro for coding?
Both are viable for coding. Anthropic's strongest reasoning and coding (Claude Opus 5.5) vs Thinking mode with visible chain-of-thought (DeepSeek V4 Pro) — pick based on which strength matters more for your workload.
Neither of these? See Claude Opus 5.5 alternatives or DeepSeek V4 Pro alternatives.
What related comparisons help choose between Claude Opus 5.5 and DeepSeek V4 Pro?
Pricing verified 2026-08-14. Specs verified 2026-08-14.