Last updated: October 10, 2026

Synthesia Syren: turn a prompt into a full video

On October 9, 2026 Synthesia launched Syren in beta: describe a video or hand it a document, and an AI agent writes the whole video as code, with motion graphics, avatars, voiceover, music and b-roll. You change it by chatting instead of starting over.

What Syren does

• Starts from anything. A prompt, a preset, or your own documents, images, videos, PowerPoint files or YouTube links.
• Builds the whole video. The agent writes the video as code and the rendering engine plays it back live, so you watch it take shape.
• Full production. Motion graphics, animation, AI avatars, voiceover, music and b-roll, horizontal or vertical, up to three minutes.
• Edit by chat. A new editor with playback and a transcript view; you ask for changes instead of rebuilding.
• On brand. Guide the look with brand assets, a reference video or a written brand description.
• Nothing to install. Videos render in the browser inside Synthesia.

Source: Synthesia: Introducing Syren (Oct 9, 2026)

How to make a video with Syren

1. Sign in to Synthesia (a free account works) and click the Syren button in the left-hand navigation.
2. Start from a prompt, pick a preset, or upload what you already have: a document, slides, images, a video or a YouTube link.
3. Add your brand assets or a reference video if the result has to match your style.
4. Watch the agent build the video live in the browser.
5. Ask for changes in the chat ("make the intro shorter", "switch to vertical", "use a calmer voice") and review them with playback or the transcript.
6. Export when you are happy. Generation uses credits from your account.

Source: Synthesia: Introducing Syren (Oct 9, 2026)

Prompt-to-video examples to start from

Synthesia has not published an official prompt guide for Syren. These are our own starting points. Give it the audience, the length, the format and the message, and attach source material when you have it.

Make a 60-second horizontal launch video for our new budgeting app. Audience: young professionals. Open with the problem (money disappearing every month), show three features with motion graphics, and end with a call to download. Upbeat music, friendly voiceover.

Turn the attached two-page PDF into a 90-second explainer for customers who have never heard of us. Use an avatar presenter, simple animated diagrams for each step, and on-screen captions.

Create a 30-second vertical video for Instagram Reels announcing our summer sale: 20% off everything this weekend. Bold text animations, fast cuts, energetic music, no avatar.

Convert the attached PowerPoint into a 2-minute video. Keep our brand colours, have an avatar present each slide, and add b-roll where a slide is only text.

Follow up in the chat to adjust: pacing, voice, music, aspect ratio or one specific scene.

Syren vs the classic Synthesia editor

This split is how Synthesia itself describes the two.

Source: Synthesia: Introducing Syren (Oct 9, 2026)

Pricing, access and limits

• Available in beta for free, self-serve and all Enterprise customers.
• Credit-based. Launch credits let every customer make a first video. Synthesia has not published how many credits a Syren video uses.
• Enterprise admins can turn Syren off for the whole organisation.
• Videos are capped at three minutes.
• Learning a company’s brand from its existing videos (graphics, motion style and pacing) is announced as coming soon, not available yet.

Source: Synthesia: Introducing Syren (Oct 9, 2026)

Syren alternatives

If you need full control over every frame, you can also have a coding model write a video as code and render it yourself, which is the same idea Syren uses under the hood. Our Opus 5.5 video guide shows the prompts and the render step.

Opus 5.5 video examples and prompts · ChatGPT Intelligent UI

Independent guide, not affiliated with Synthesia. Facts come from Synthesia's October 9, 2026 launch post, checked on October 10, 2026. The example prompts are ours.