DeepSeek V4.1 Flash is here: faster coding, native vision, and iolys compatibility
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.
Released on September 10, 2026, 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.
Use it in iolys to explore code, refactor a service, or write tests for your C# and .NET projects.
Native vision
Native vision 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. Turn thinking 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% | $0.006 · ↓ −70% | $0.02 |
| Uncached input | $0.15 · ↓ −25% | $0.30 · ↑ +50% | $0.20 |
| Output | $0.60 · ↓ −50% | $1.20 · = 0% | $1.20 |
Compared with Luna: ↓ cheaper, ↑ more expensive, = same price.
Sources: DeepSeek pricing and GPT-5.6 Luna specifications.
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.
Total task cost depends on token usage and retries.
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 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 or install iolys for Visual Studio.