Claude Sonnet 5 vs DeepSeek V4.1 Flash
At a Glance
| Compare | Claude Sonnet 5Anthropic |  DeepSeek V4.1 FlashDeepSeek |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v2.5 | #26 of 4660.1 score · 2/3 sources · provisional · missing ARC-AGI-2 · full-core range 40.0–73.4 | UnrankedNot in the 46-model eligible cohort |
| CostLower is better · Published-token output estimate | #29 of 44$0.194 per LiveBench case | #5 of 44$0.022 per LiveBench case |
| EfficiencyHigher is better · MM Efficiency v1.5 | #30 of 3847.4 score · 2/3 sources · provisional · missing ARC-AGI-2 · full-core range 37.4–54.0 | UnrankedNot in the 38-model eligible cohort |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $2.00Anthropic ↗ · Sep 3, 2026 | $0.15DeepSeek ↗ · Sep 10, 2026 |
| Output priceFrom · USD / 1M tokens | $10.00Anthropic ↗ · Sep 3, 2026 | $0.60Deepinfra ↗ · Sep 22, 2026 |
| Context windowMaximum documented tokens | 1,000K | 1,049K |
| Model facts checked | Aug 28, 2026View model evidence → | Sep 10, 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 5 | DeepSeek-V4.1-Flash |
|---|---|---|
| LMArena Agent Arenaagent-2026-09-15-d25aabda0010 · outcome_score · statistical tie | 5.97100% of row best · score · Claude Sonnet 5 (High); 95% CI [4.35064977, 7.58850066]; sessions 30631; observations 3176952; rank 9 | 4.8899% of row best · score · Deepseek V4.1 Flash (Max); 95% CI [3.54852933, 6.21109128]; sessions 20080; observations 2295632; rank 12 |
| LiveBench2026-06-25 · overall · leader | 80.0196% of row best · percent · claude-sonnet-5-xhigh-effort · 19,428 output tokens / case | 83.20100% of row best · percent · deepseek-v4.1-flash-max · 36,355 output tokens / case |
| ToneBench2026-09-11-10-task-4ef099199c9c · overall_score · unverified | 86.5198% of row best · points · Claude Sonnet 5 (max effort) · 71,003 output tokens / case | 88.03100% of row best · points · DeepSeek V4.1 Flash (max) · 18,199 output tokens / case |
| Overall ResultCounted from the protocol-matched rows above · 1 tie | 0 benchmark winsNo overall winner | 1 benchmark winNo overall winner |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Quality Versus Estimated Output Cost
Side-by-Side Facts
| Field | Claude Sonnet 5 | DeepSeek-V4.1-Flash |
|---|---|---|
| Developer | Anthropic | DeepSeek |
| Family | Claude 5 | Deepseek V4 1 |
| Model | Claude Sonnet 5 | DeepSeek-V4.1-Flash |
| Version | Claude Sonnet 5 | DeepSeek-V4.1-Flash |
| Lifecycle | active | active |
| Released | 2026-06-30 | 2026-09-10 |
| Knowledge cutoff | Unknown | Unknown |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
| Context window | 1,000K | 1,049K |
| Total parameters | Unknown | 763.2B |
| Active parameters | Unknown | Unknown |
| License | Unknown | mit |
| Open weights | No | Yes |
| API available | Yes | Yes |
| Self-hostable | No | Yes |
| Provider access | Anthropic (Standard), Deepinfra (Standard), Openrouter (Standard) | DeepSeek (Standard), Deepinfra (Standard), Together Ai (Standard) |
| Capabilities | chat, generation, reasoning, tools | agents, chat, fim, generation, reasoning, responses, structured_outputs, tools, vision |
| Architecture design | Unknown | Causal Encoder-Decoder (20 encoder + 20 decoder layers) |
| Backbone parameters | Unknown | 552000000000 parameters |
| Active parameters during decode | Unknown | 16000000000 parameters |
| Active parameters during prefill | Unknown | 8000000000 parameters |
| Pre-training corpus | Unknown | 45000000000000 tokens |
| Reasoning effort range | Unknown | 1–100 |
| Routed experts per MoE layer | Unknown | 384 experts |
| Routed experts per token | Unknown | 6 experts |
| Transformer layers | Unknown | 40 layers |
Claude Sonnet 5 Capabilities
DeepSeek V4.1 Flash Capabilities
Related Comparisons
All image comparisons →| A | Pair | B | Context |
|---|---|---|---|
Claude Sonnet 4.6Anthropic | vs | Claude Sonnet 5Anthropic | family variantsimage, text |
Claude Sonnet 5Anthropic | vs | DeepSeek-V4-FlashDeepSeek | cross-developer peerstext |
Claude Sonnet 5Anthropic | vs |  GPT-6 AstraOpenAI | cross-developer peersimage, text |
Claude Fable 5.1Anthropic | vs | Claude Sonnet 5Anthropic | family variantsimage, text |
Claude Sonnet 5Anthropic | vs |  Gemini 3.1 ProGoogle DeepMind | cross-developer peerstext |
Claude Sonnet 5Anthropic | vs | Grok 4.6xAI | cross-developer peersimage, text |
Claude Sonnet 5Anthropic | vs |  Qwen3.8-MaxQwen | cross-developer peersimage, text |
Claude Sonnet 5Anthropic | vs |  Kimi-K3Moonshot AI | cross-developer peersimage, text |
 MiniMax-M3MiniMax | vs | Claude Sonnet 5Anthropic | cross-developer peersimage, text |
Claude Sonnet 5Anthropic | vs |  GLM-5.3Z.ai | cross-developer peerstext |
Claude Sonnet 5Anthropic | vs |  Hy4 previewTencent | cross-developer peerstext |
Claude Sonnet 5Anthropic | vs | Seed 2.1 ProByteDance Seed | cross-developer peersimage, text |
Primary Evidence
Sources and Freshness
Questions
Claude Sonnet 5 vs DeepSeek V4.1 Flash FAQs
Is Claude Sonnet 5 or DeepSeek V4.1 Flash better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Sonnet 5 and DeepSeek V4.1 Flash, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Sonnet 5 or DeepSeek V4.1 Flash?+
Claude Sonnet 5 is $2.00 and DeepSeek V4.1 Flash is $0.15 per million tokens, so DeepSeek V4.1 Flash is cheaper on this metric. Claude Sonnet 5 is $10.00 and DeepSeek V4.1 Flash is $0.60 per million tokens, so DeepSeek V4.1 Flash is cheaper on this metric.
Which has a larger context window, Claude Sonnet 5 or DeepSeek V4.1 Flash?+
DeepSeek V4.1 Flash has the larger sourced context window. Claude Sonnet 5 supports 1,000K and DeepSeek V4.1 Flash supports 1,049K.
Which performs better in benchmarks, Claude Sonnet 5 or DeepSeek V4.1 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 5 or DeepSeek V4.1 Flash be self-hosted?+
DeepSeek V4.1 Flash is the only model in this pair currently marked as self-hostable. Claude Sonnet 5 is not marked open weight; DeepSeek V4.1 Flash is open weight.
Can Claude Sonnet 5 and DeepSeek V4.1 Flash understand images?+
Claude Sonnet 5 is documented with image input; DeepSeek V4.1 Flash is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Sonnet 5 or DeepSeek V4.1 Flash?+
DeepSeek V4.1 Flash has the larger sourced maximum output: Claude Sonnet 5 supports 128K and DeepSeek V4.1 Flash supports 393K output tokens.
Do Claude Sonnet 5 and DeepSeek V4.1 Flash support reasoning and tool use?+
Claude Sonnet 5: reasoning, tool calling, and image input. DeepSeek V4.1 Flash: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Sonnet 5 or DeepSeek V4.1 Flash?+
Claude Sonnet 5 has 3 sourced provider routes; DeepSeek V4.1 Flash has 3, a tie.
Which offers better value, Claude Sonnet 5 or DeepSeek V4.1 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.