Claude Sonnet 4.5 vs DeepSeek V4 Flash
At a Glance
| Compare | Claude Sonnet 4.5Anthropic |  DeepSeek V4 FlashDeepSeek |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v2.5 | #36 of 4627.7 score · 2/3 sources · provisional · missing LiveBench · full-core range 18.5–51.8 | UnrankedNot in the 46-model eligible cohort |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $3.00Anthropic ↗ · Sep 3, 2026 | $0.0868Openrouter ↗ · Aug 28, 2026 |
| Output priceFrom · USD / 1M tokens | $15.00Anthropic ↗ · Sep 3, 2026 | $0.1736Openrouter ↗ · Aug 28, 2026 |
| Context windowMaximum documented tokens | 200K | 1,049K |
| Model facts checked | Sep 3, 2026View model evidence → | Aug 28, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | Claude Sonnet 4.5 | DeepSeek-V4-Flash |
|---|---|---|
| ARC-AGI-1verified-v1-ba05d69f6453 · verified_score · leader | 63.6772% of row best · percent · Claude Sonnet 4.5 (Thinking 32K) | 89.00100% of row best · percent · DeepSeek V4 Flash 0731 (Max) |
| ARC-AGI-2verified-v2-6c676fa3e9af · verified_score · leader | 13.6122% of row best · percent · Claude Sonnet 4.5 (Thinking 32K) | 61.39100% of row best · percent · DeepSeek V4 Flash 0731 (Max) |
| LMArena Text Arenatext-2026-09-13-d25aabda0010 · arena_rating · statistical tie | 1,433.94100% of row best · rating · claude-sonnet-4-5-20250929-high-32k; 95% CI [1431.13982742, 1436.74901697]; votes 80980; rank 81 | 1,431.79100% of row best · rating · deepseek-v4-flash; 95% CI [1427.66110387, 1435.91557810]; votes 48887; rank 83 |
| ToneBench2026-09-11-10-task-4ef099199c9c · overall_score · unverified | 77.2599% of row best · points · Claude Sonnet 4.5 · 7,415 output tokens / case | 78.00100% of row best · points · DeepSeek V4 Flash (xhigh) · 12,709 output tokens / case |
| Overall ResultCounted from the protocol-matched rows above · 1 tie | 0 benchmark winsNo overall winner | 2 benchmark winsNo overall winner |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | Claude Sonnet 4.5 | DeepSeek-V4-Flash |
|---|---|---|
| Developer | Anthropic | DeepSeek |
| Family | Claude 4 | Deepseek V4 Flash |
| Model | Claude Sonnet 4.5 | DeepSeek-V4-Flash |
| Version | Claude Sonnet 4.5 | DeepSeek-V4-Flash |
| Lifecycle | active | retired |
| Released | 2025-09-29 | 2026-04-24 |
| Knowledge cutoff | 2025-01-01 | Unknown |
| Input modalities | Text, Image | Text |
| Output modalities | Text | Text |
| Context window | 200K | 1,049K |
| Total parameters | Unknown | 290.9B |
| Active parameters | Unknown | 13B |
| License | Unknown | mit |
| Open weights | No | Yes |
| API available | Yes | Yes |
| Self-hostable | No | Yes |
| Provider access | Anthropic (Standard) | DeepSeek (Standard), Deepinfra (Standard), Fireworks Ai (Standard), Hugging Face (Standard), Openrouter (Standard) |
| Capabilities | chat, generation, reasoning, structured_outputs, tools | chat, generation, reasoning |
Claude Sonnet 4.5 Capabilities
DeepSeek V4 Flash Capabilities
Related Comparisons
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|---|---|---|---|
Claude Sonnet 4.5Anthropic | vs |  GPT-6 AstraOpenAI | cross-developer peersimage, text |
Claude Fable 5.1Anthropic | vs | Claude Sonnet 4.5Anthropic | family variantsimage, text |
Claude Sonnet 4.5Anthropic | vs |  Gemini 3.1 ProGoogle DeepMind | cross-developer peerstext |
Claude Sonnet 4.5Anthropic | vs | DeepSeek-V4.1-FlashDeepSeek | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs | Grok 4.6xAI | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs |  Qwen3.8-MaxQwen | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs |  Kimi-K3Moonshot AI | cross-developer peersimage, text |
 MiniMax-M3MiniMax | vs | Claude Sonnet 4.5Anthropic | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs |  GLM-5.3Z.ai | cross-developer peerstext |
Claude Sonnet 4.5Anthropic | vs |  Hy4 previewTencent | cross-developer peerstext |
Claude Sonnet 4.5Anthropic | vs | Seed 2.1 ProByteDance Seed | cross-developer peersimage, text |
Claude Sonnet 4.5Anthropic | vs |  Mistral Large 3Mistral AI | cross-developer peersimage, text |
Primary Evidence
Sources and Freshness
Questions
Claude Sonnet 4.5 vs DeepSeek V4 Flash FAQs
Is Claude Sonnet 4.5 or DeepSeek V4 Flash better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Sonnet 4.5 and DeepSeek V4 Flash, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Sonnet 4.5 or DeepSeek V4 Flash?+
Claude Sonnet 4.5 is $3.00 and DeepSeek V4 Flash is $0.0868 per million tokens, so DeepSeek V4 Flash is cheaper on this metric. Claude Sonnet 4.5 is $15.00 and DeepSeek V4 Flash is $0.1736 per million tokens, so DeepSeek V4 Flash is cheaper on this metric.
Which has a larger context window, Claude Sonnet 4.5 or DeepSeek V4 Flash?+
DeepSeek V4 Flash has the larger sourced context window. Claude Sonnet 4.5 supports 200K and DeepSeek V4 Flash supports 1,049K.
Which performs better in benchmarks, Claude Sonnet 4.5 or DeepSeek V4 Flash?+
There is no overall benchmark winner: An overall winner requires at least two decisive benchmarks from at least two original publishers.
Can Claude Sonnet 4.5 or DeepSeek V4 Flash be self-hosted?+
DeepSeek V4 Flash is the only model in this pair currently marked as self-hostable. Claude Sonnet 4.5 is not marked open weight; DeepSeek V4 Flash is open weight.
Can Claude Sonnet 4.5 and DeepSeek V4 Flash understand images?+
Claude Sonnet 4.5 is documented with image input; DeepSeek V4 Flash is not documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Sonnet 4.5 or DeepSeek V4 Flash?+
Neither has a larger sourced maximum output. Claude Sonnet 4.5 is 64K and DeepSeek V4 Flash is —.
Do Claude Sonnet 4.5 and DeepSeek V4 Flash support reasoning and tool use?+
Claude Sonnet 4.5: reasoning, tool calling, and image input. DeepSeek V4 Flash: reasoning. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Sonnet 4.5 or DeepSeek V4 Flash?+
Claude Sonnet 4.5 has 1 sourced provider route; DeepSeek V4 Flash has 5, so DeepSeek V4 Flash has broader tracked availability.
Which offers better value, Claude Sonnet 4.5 or DeepSeek V4 Flash?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.