{"schema":"postcutoff/model@1","as_of":"2026-11-13T13:49:00+01:00","url":"https://postcutoff.com/m/deepseek-v4-1-flash/","md":"https://postcutoff.com/m/deepseek-v4-1-flash/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"human editor","policy":"https://postcutoff.com/about/"},"license":null,"id":"deepseek-v4-1-flash","name":"DeepSeek-V4.1-Flash","org":"DeepSeek","family":"DeepSeek V4","released":"2026-09-10","status":"current","type":"reasoning-llm","modality_in":["text","image"],"modality_out":["text"],"open_weights":true,"model_license":"mit","context_window":1000000,"max_output":384000,"knowledge_cutoff":null,"pricing":{"input":0.3,"output":1.2,"cache_read":0.006,"unit":"per 1M tokens (USD), peak-hour list price; off-peak is half (input 0.15, output 0.6, cache hit 0.003). Peak = 01:00-04:00 and 06:00-10:00 UTC Mon-Fri","source":"https://api-docs.deepseek.com/quick_start/pricing"},"price_line":"$0.30 in, $1.20 out per 1M tokens","access":[{"provider":"DeepSeek API","model_id":"deepseek-flash","endpoint":"https://api.deepseek.com","docs":"https://api-docs.deepseek.com/quick_start/pricing"},{"provider":"DeepSeek API (Anthropic format)","model_id":"deepseek-flash","endpoint":"https://api.deepseek.com/anthropic","docs":"https://api-docs.deepseek.com/quick_start/pricing"},{"provider":"Alibaba Cloud Model Studio","model_id":"deepseek-v4.1-flash","docs":"https://www.alibabacloud.com/help/en/model-studio/models"},{"provider":"OpenRouter","model_id":"deepseek/deepseek-v4.1-flash","url":"https://openrouter.ai/deepseek/deepseek-v4.1-flash"},{"provider":"Hugging Face","url":"https://huggingface.co/deepseek-ai/DeepSeek-V4.1-Flash"},{"provider":"Web app","url":"https://chat.deepseek.com"}],"capabilities":[{"name":"Native vision in the Flash tier","detail":"First DeepSeek Flash model with native multimodal (image) understanding built in; replaced the separate V4-Flash-Vision-Exp.","first":false,"discovered":"launch","source":"https://api-docs.deepseek.com/updates"},{"name":"Causal Encoder-Decoder (CED) architecture","detail":"552B-backbone MoE that activates only ~8B params per token in prefill and ~16B in decode, aimed at input-heavy agentic workloads.","first":false,"discovered":"launch","source":"https://huggingface.co/deepseek-ai/DeepSeek-V4.1-Flash"},{"name":"Tiny KV cache (CSA2 + FP4 KV)","detail":"Compressed Sparse Attention 2 and FP4 main KV cache cut the global KV cache to ~890 bytes/token, about 1/4 of V4-Flash.","first":false,"discovered":"launch","source":"https://huggingface.co/deepseek-ai/DeepSeek-V4.1-Flash"},{"name":"Hybrid thinking with effort levels","detail":"One model id serves thinking (default) and non-thinking modes; reasoning effort low/high/max.","first":false,"discovered":"launch","source":"https://api-docs.deepseek.com/updates"},{"name":"Multiple API protocols","detail":"Same model served via OpenAI Chat Completions, OpenAI Responses (Codex-adapted) and Anthropic Messages formats.","first":false,"discovered":"launch","source":"https://api-docs.deepseek.com/quick_start/pricing"}],"entry":null,"notes":"Call as deepseek-flash (since Oct 17, 2026 it serves the DeepSeek-V4.1-Flash-1017 snapshot, same price; weights at huggingface.co/deepseek-ai/DeepSeek-V4.1-Flash-1017, OpenRouter id deepseek/deepseek-v4.1-flash-1017). Legacy ids deepseek-v4-flash and deepseek-v4-flash-vision-exp are routed here and billed at Flash price. Knowledge cutoff not published.","verified":"2026-10-17","body_md":"DeepSeek's cheapest current model: agentic coding, long-context (1M) work and image understanding at very low cost. Schedule batch jobs off-peak for 50% off.\n\n```bash\ncurl https://api.deepseek.com/chat/completions \\\n -H \"Authorization: Bearer $DEEPSEEK_API_KEY\" -H \"Content-Type: application/json\" \\\n -d '{\"model\":\"deepseek-flash\",\"messages\":[{\"role\":\"user\",\"content\":\"Hello\"}]}'\n```\n\nSources: https://api-docs.deepseek.com/quick_start/pricing · https://api-docs.deepseek.com/updates · https://huggingface.co/deepseek-ai/DeepSeek-V4.1-Flash","page_url":"https://postcutoff.com/m/deepseek-v4-1-flash/","events_after":null,"major_after":null,"historic_after":null,"missing_at_launch":null,"events_since_release":1530,"you_url":"https://postcutoff.com/you/deepseek-v4-1-flash/","briefings":null}