How to Turn a Past Stream into Shorts with Castream AI Shorts

Your stream ended an hour ago. The chat was great, the energy was there, and now the recording is just sitting there. This is the easiest possible starting point for AI Shorts — because the stream is already recorded, and its chat is already part of the deal.

Every Castream stream is recorded. That means you don't have to upload anything, find a file, or remember where you saved it. Pick the stream, and AI Shorts can get to work.

Before you start

You need two things: a past Castream stream, and enough credits for its length. Remember, 1 credit = 1 minute of video, however many shorts come out of it. A 45-minute stream uses 45 credits.

Shorts are kept for 30 days, and stream recordings are also kept for 30 days — so don't leave a stream you love sitting untouched until the window closes. Download the shorts you want to keep for good.

Step by step

1. Pick your past stream. Choose the stream you want shorts from. If you streamed to several platforms at once, the chat from every platform counts — it's all lined up on one timeline.

2. Let AI Shorts find the moments. It listens to the whole stream and reads your chat, picking the strongest moments — the ones where viewers laughed, reacted, or asked for more. How that works is explained in How Castream AI Shorts Finds Your Best Moments.

3. Review what comes back. You get up to 3 shorts, up to 60 seconds each, in vertical 9:16 format. Each comes with word-by-word captions, an on-screen hook, a title, a description, and hashtags. Videos with few strong moments may give fewer.

4. Keep, edit, or delete. Keep the shorts you like and delete the rest. If a caption word is wrong, fix it in the web caption editor — edits never use credits. See How to Edit AI Shorts Captions on the Web.

5. Download or share. Save a short to your phone, or share it to TikTok, Instagram, or YouTube from the share sheet. The posting details — hooks, titles, and hashtags — are covered in AI Shorts Titles, Hooks and Hashtags: How to Post Your Shorts.

Which stream should you pick first?

Start with a stream where chat was active. A church service where the congregation responded, a gaming session where chat lit up at one play, a fitness class where viewers kept asking questions — those are the streams where the chat signal does the most work for you.

A quiet stream still works. AI Shorts listens to the whole video either way; you just lean more on the audio and content, and less on chat reactions. But if you're testing the feature for the first time, an active-chat stream is the best demo of what makes it different.

What if your stream is long?

Long is fine. That's the whole point — nobody wants to rewatch a two-hour stream hunting for three clips. The credit cost scales with length (a 60-minute stream is 60 credits), not with how many shorts come out, so a long stream with three great moments costs the same as a long stream with one.

Check your balance against the plan limits before you start: a free trial includes 15 credits, Creator includes 50 a month, and Pro includes 200 a month. The full math is in Castream AI Shorts Credits and Pricing Explained.

A note on timing

Make shorts while the stream is still fresh in your mind — and while the recording is still within its 30-day window. The best time to post a clip from a stream is usually soon after the stream itself, when your audience still remembers it.

For the complete overview of AI Shorts, see Castream AI Shorts: Turn Streams and Phone Videos into Vertical Shorts and Castream AI Shorts.