DeepSeek V4.1 Flash hands-on tests and comparisons

A user's test reports 91.5% accuracy on 251 tasks for $1.8 total, but 85% of output tokens go to reasoning, with five web demos burning 40K tokens before writing any code.

On the same nested SVG animation prompt, the poster finds Fable 5.5 clearly better on physical logic and visual detail, while V4.1 Flash 1017 trails but remains comparable.

A user plans to cancel Devin and use DeepSeek V4.1 Flash as a sub-model via the official API instead.

Coding and agent tasks are more decisive and cost 70-90% less than Opus/GPT, but speed is still slow, hallucinations persist, and other harnesses can loop on verification.

Official 1017 release lifts Terminal-Bench 4.0 from 31.2 to 42.3 and ships MIT-licensed weights; the same thread also notes an OpenCode Console breach.

In a blind frontend test drawing a zebra riding a bicycle in SVG, DeepSeek rendered the stripes but its limb motion and mechanical structure looked stiff, while Gemini led on composition, aesthetics and geometry.

A user ran a commandcode fingerprint test on V4.1 Flash, got 71%, and suspects the model is diluted or not the native release.

A roundup of the 1017 update: DeepSWE 77.0 edges out Opus 5 with no price increase, Search & Fetch APIs launch at $0.75 per 1,000 calls, and MIT weights are on Hugging Face though prompt encoding is DIY.

The lead item in a six-story tech digest says the October 17 V4.1 Flash-1017 update reached web, app and API with higher benchmark scores, shorter task times and outputs, and stronger from-scratch project building.

A user reports that the DeepSeek V4.1 Flash offered in OpenCode Go has not been upgraded to the 1017 release, so version differs from the new model.

The author notes DeepSWE 77.0 tops the official table (Opus 5 at 74.0) but Terminal-Bench 4.0's 42.3 trails Opus 5's 51.8, with Opus 5 ahead in 6 of 11 items, all self-reported, so real tasks should decide.

The post cites DeepSWE v1.1 77.0, Terminal-Bench 4.0 rising from 31.2 to 42.3, $0.15/$0.60 API pricing, a third of the previous cost per task, and praises quoted 3D work.