DeepSeek V4.1 Flash is an efficient model that performs on-par with Opus 5 and GPT-5.6-Sol, and outperforms its older and much larger sibling DeepSeek V4 Pro.

It's also very, very fast: in the first 24hrs, we've averaged over 150tps on V4.1-Flash, and we expect to get it even faster and cheaper over the coming weeks as we improve our serving infrastructure.

This is the first time we've self-hosted a DeepSeek model on the subscription, and we're excited to support it!

And like the GLM-5.3-Flash release a couple of weeks ago, DeepSeek V4.1 Flash is also the first stable, non-experimental version of the DeepSeek family that supports vision on uploaded images. While models can go surprisingly far without actually being able to see, it becomes much more difficult to fix layout issues for complex visual hierarchies or fix generated slide decks if it can't, well, actually see the end result. Since DS V4.1 Flash can see, it can find issues in its own outputs from a visual standpoint and automatically fix them.

There are tons of ways you can use it:

* In Claude Code, [using our Anthropic-compatible API.](https://dev.synthetic.new/docs/guides/claude-code)
* In OpenCode, [Octofriend](https://github.com/synthetic-lab/octofriend), Crush, OpenClaw and more, using our standard OpenAI-compatible API.
* On [our website](https://synthetic.new/), of course!
* And pretty much any other way you can dream of, using either of our API options. All with higher rate limits than Anthropic or OpenAI using our subscription.

DeepSeek V4.1 Flash is available via the Synthetic subscription