Most "AI video editors" upload your footage to their servers and bill you a monthly subscription for the privilege. There is a better model: bring your own key, keep the video on your device, and pay only your provider's (often free) rate. Here is how it works in Zella.

How bring-your-own-key works

Zella's AI Assistant does not run its own paid AI service. Instead, you connect it to a language-model provider you already control:

  • Groq - free, fast, no credit card.
  • Google Gemini - generous free tier.
  • Cerebras - free and fast.
  • Ollama - runs a model locally on your Mac, no key and no internet.

You paste your key once. It is stored in the macOS Keychain, never in a plain-text file, never logged.

A typed instruction above a timeline, and the same timeline below with one clip removed.

The standard worth writing to is the one Google publishes: helpful, reliable, people-first content, which is explicit that how something was produced matters less than whether it was worth making.

What actually gets sent

This is the part that matters for privacy. When you type a request:

  1. Zella sends your text (the instruction) and a compact summary of the project - durations, the clip list, how many captions exist - to your chosen provider.
  2. The model replies with the editing actions to run.
  3. Zella runs them locally on your timeline.

Your video frames, your audio, and your files never leave your device. Zella uploads nothing. If you use Ollama, even the text request stays on-device.

Compare that to a typical cloud editor, which ships your entire recording to its servers to process. For internal demos, client work, or anything under NDA, local-only is not a nice-to-have - it is the requirement.

Setting it up

  1. Open a project in Zella and click the Assistant tab, then the gear icon.
  2. Choose a provider and click Get free key.
  3. Paste the key, click Save Key, then Test Connection.
  4. Start typing your edits.

Full walkthrough in the AI Assistant documentation.

Why bring-your-own-key is cheaper

Subscription AI editors fold the model cost into a recurring fee whether you edit once a month or fifty times. With your own key you pay the provider directly - and on free tiers that is often nothing. Zella itself is a one-time purchase with a free plan, so there is no subscription stacked on top.

What you can do with the assistant

71 editing actions, all driven by typing: remove silences and filler words, add captions, grade colour, remove and replace backgrounds, add music and sound effects, reframe to 9:16 / 1:1 / 16:9, and export.

You do not have to learn a syntax for any of it. "Remove the silences", "Can you take out the boring quiet bits?" and "Cut the dead air, please" all reach the same action, and you can chain a whole sequence in one sentence: "remove the dead air, add captions and make it vertical."

Two things worth knowing before you weigh this against a subscription. The Assistant is not part of Pro - it is free on every tier, on both platforms. And it is not Mac-only: the same bring-your-own-key Assistant runs on iPhone, where the key also stays on the device and only your typed prompt is ever sent. Ollama is the one exception, since running the model locally is a Mac thing. See how to edit a video by typing for examples.

Frequently asked questions

Where is my API key stored? In the macOS Keychain - never in a plain-text file, and never logged. You paste it once during setup and Zella reads it from there.

Can I use this with no internet at all? Yes. Point the assistant at a local Ollama model and even the text of your request stays on your Mac, because there is no provider to call.

What does the provider actually see? Your typed instruction plus a compact summary of the project: durations, the clip list, how many captions exist. Never the frames, the audio, or your files.

Does Zella charge per edit or per minute? No. Zella runs no AI service of its own, so you pay your chosen provider directly, and Groq, Gemini and Cerebras all have free tiers. Zella itself is a one-time purchase with a free plan underneath it.

How do I confirm the key works? Click Test Connection in the Assistant settings after you save the key. If it passes, you can start typing edits.

Bottom line

You do not have to choose between AI convenience and privacy. Bring your own key, keep your footage on your device, and let the assistant do the editing. Get Zella free and connect a key in under a minute.