DeepSeek V4.1 Flash hands-on tests and comparisons

XenoSpectrum reports DeepSeek V4.1 Flash surpasses Claude Opus 5 on code repair benchmarks while keeping API pricing unchanged.

A user says that despite DeepSeek V4.1 Flash being cheap with strong benchmarks, most users still prefer Haiku 5.5, showing how good Claude 5.5 models are.

shiguredo/deepseek-harness has been updated to the latest release, which the author says is needed to use DS V4.1 F 1017.

A video made with V4.1 Flash 1017 demonstrates wish-style coding: state only the desired result without describing implementation, so non-programmers can ship a product.

On the official API with thinking on, fixing json_schema to json_object raised scores to 92/100 at temp 1.0 and 90/100 at temp 0, up from 87 and 85.

DeepSeek says the new model scores higher, runs faster and outputs less, with MIT-licensed weights on Hugging Face and Search/Fetch APIs open to all at $0.75 per 1,000 calls.

Usage feedback: a user wants DeepSeek-V4.1-Flash-1017 available for free inside OpenCode.

Benchmarks show Terminal-Bench 4.0 up from 31.2 to 42.3, DeepSWE 74.2 to 77.0 and Automation-Bench 54.8 to 60.5, with shorter outputs, lower cost and MIT-licensed weights on Hugging Face.

A post argues DeepSeek V4.1 Flash codes at roughly Opus 5 level for about 2% of the cost at 200+ tps, fueling a pricing race among labs.

DeepSeek opened its search and fetch API free through Oct 31 for Claude Code, Codex and DeepSeek Harness (normally $0.75 per 1,000 searches), while V4.1 Flash tokens still bill from $0.15 per 1M input.

Official announcement cites benchmark gains, faster task completion and shorter output time; live on web, app and API, with Harness v0.2.1-rc.1+ required.

The post says OpenCode, a terminal coding assistant with selectable models, currently offers DeepSeek V4.1 Flash for free.