---
title: "DeepSeek V4.1 Flash is here: faster coding, native vision, and iolys compatibility"
description: "Use DeepSeek V4.1 Flash with iolys in Visual Studio: stronger coding capabilities, native vision, a 1M-token context window, and lower API costs than V4 Pro."
language: "en"
url: "https://getiolys.com/blog/2026/09/10/deepseek-v4-1-flash-iolys"
date: "2026-09-10"
updated: "2026-09-10"
author: "J\u00E9r\u00F4me Giacomini"
tags: ["DeepSeek",".NET","C#","Artificial intelligence","Visual Studio","iolys"]
---

# DeepSeek V4.1 Flash is here: faster coding, native vision, and iolys compatibility

Released on [September 10, 2026](https://api-docs.deepseek.com/updates/#date-2026-09-10), **DeepSeek V4.1 Flash is compatible with iolys**. Use it in Visual Studio with your DeepSeek API key.

## Better coding, faster responses

DeepSeek reports faster execution and stronger coding results than V4 Pro: **90.6 vs 87.9 on Terminal-Bench 2.1** and **65.4 vs 61.5 on NL2Repo-Bench**. [Provider benchmarks](https://api-docs.deepseek.com/updates/).

Use it in iolys to explore code, refactor a service, or write tests for your C# and .NET projects.

## Native vision

**[Native vision](https://api-docs.deepseek.com/updates/#date-2026-09-10)** lets you ask about screenshots and charts. Select Flash with the **Vision** badge in iolys, then attach your image.

## More context, adjustable reasoning

Combine code, logs, and documentation in a **[1M-token context window](https://api-docs.deepseek.com/quick_start/pricing/)**. Turn [thinking](https://api-docs.deepseek.com/guides/thinking_mode/) off or choose `low`, `high`, or `max` effort to balance speed and depth.

## Pricing vs GPT-5.6 Luna

**Off-peak, Flash costs less than Luna across all three token rates.** Standard API prices in USD per million tokens, checked September 10, 2026:

| Token type | V4.1 Flash, off-peak | V4.1 Flash, peak | GPT-5.6 Luna (reference) |
| --- | ---: | ---: | ---: |
| Cached input | $0.003 · **↓ −85%**{.price-change .price-change--lower} | $0.006 · **↓ −70%**{.price-change .price-change--lower} | $0.02 |
| Uncached input | $0.15 · **↓ −25%**{.price-change .price-change--lower} | $0.30 · **↑ +50%**{.price-change .price-change--higher} | $0.20 |
| Output | $0.60 · **↓ −50%**{.price-change .price-change--lower} | $1.20 · **= 0%**{.price-change .price-change--same} | $1.20 |

Compared with Luna: **↓ cheaper**{.price-change .price-change--lower}, **↑ more expensive**{.price-change .price-change--higher}, **= same price**{.price-change .price-change--same}.

Sources: [DeepSeek pricing](https://api-docs.deepseek.com/quick_start/pricing/) and [GPT-5.6 Luna specifications](https://developers.openai.com/api/docs/models/gpt-5.6-luna).

**DeepSeek peak hours:** Monday–Friday, 01:00–04:00 and 06:00–10:00 UTC. All other hours are off-peak.

**Luna:** above 272K input tokens, the full request costs 2× for input and 1.5× for output. [Cache writes have separate pricing](https://developers.openai.com/api/docs/models/gpt-5.6-luna).

Total task cost depends on token usage and retries.

## ![DeepSeek logo](https://getiolys.com/img/providers/deepseek.png) Use V4.1 Flash with iolys

Open **Manage Providers**, enter your DeepSeek API key, and click **Test Connection**. Select **`deepseek-flash`** to start. Usage is billed to your DeepSeek account.

![DeepSeek provider setup in iolys showing a successful connection and deepseek-flash with Tools, Vision, and Thinking capabilities.](https://getiolys.com/blog/media/2026/deepseek-v4-1-flash-iolys/images/deepseek-v4-1-flash-setup.png)

*DeepSeek Flash in iolys, with Tools, Vision, and Thinking support.*

**iolys has been updated to support DeepSeek V4.1 Flash, the latest DeepSeek release.** Update iolys to use it directly in Visual Studio.

[Explore DeepSeek in iolys](https://getiolys.com/providers/deepseek) or [install iolys for Visual Studio](https://marketplace.visualstudio.com/items?itemName=iolys.iolys-visual-studio).