How to Extend a Video With AI: Add Seconds to a Clip

Extending a video with AI means handing a finished clip to a model and getting new footage back that plays after its last frame. You keep the take you already like, describe what happens next, and the model renders the continuation instead of a fresh attempt at the same shot. This guide shows which mode actually does that, how long the clip you hand over can be, and what one extension costs at the settings you choose.

The word to watch for is extend. A rework mode also takes a finished clip, but it re-renders the clip you give it and adds nothing after its last frame: Kling O3 runs one on a clip of up to 15 seconds, which is useful for changing a scene and gives you no extra seconds. The sections below keep the two apart, because picking the wrong one spends credits on a clip that gains no extra seconds.

Key takeaways

Extend or rework: what you get back

Before you pick a model, check what it does with a finished clip. Veo 3.1 continues a clip: it renders new footage that plays after the last frame of the clip you give it, and it takes a source clip of up to 8 seconds. Kling O3 takes a clip of up to 15 seconds and reworks it from your prompt, adding nothing after its last frame. Gemini Omni also reworks a clip and adds nothing after its last frame, with no published limit on the clip it takes, and its own generated clips, not the source, run 3 to 10 seconds.

So the first question is which result you want, not which tool to open. If the clip is good and simply ends too soon, you want the continue mode. Veo 3.1 continues a source clip of up to 8 seconds. If the clip is the right length but the wrong setting, light or wardrobe, you want a rework, and the model catalogue lists what Kling O3 and Gemini Omni take in.

Before you begin

• A clip of 8 seconds or less, which is the longest source clip Veo 3.1 accepts. Save it in your Influverse gallery first.
• The right model picked before you generate; step 1 below says which. Use the Extend action on the video page.
• Enough credits for one request at the resolution and audio setting you plan to use. The cheapest Veo 3.1 request, 4 seconds at 720p, is 31 credits, so the 20 free Starter credits do not cover one on their own.
• A one line idea of what happens next in the shot: who moves, where to, and what the camera does.

Step by step: extend a clip from its last frame

By the end of these steps you'll have new footage that carries on from your clip's last frame. The steps below happen on the video page, apart from any trimming.

Step 1: Open the clip and press Extend

Go to the video page, open the clip in your gallery and press Extend. Then check that Veo 3.1 is the selected model. Veo 3.1 continues a clip and takes a source clip of up to 8 seconds. A clip that fits is ready for the next step, the prompt.

Veo 3.1 takes a source clip of up to 8 seconds, so a longer clip is over its limit. Trim a longer clip to that length or shorter first in the video editor, export it, and extend the exported copy, trimming from the front, not the end, so the ending you want continued is the one that stays.

Step 2: Write the prompt as what happens next

Describe the next beat of the action, not the clip you already have. Spend the prompt on the verb: the clip supplies the frame, and the prompt supplies what moves. "She turns from the window, picks up the cup and walks out of frame left" gives the model a direction, a subject and an exit. "A woman standing by a window" gives it a reason to stand still for a few more seconds.

Keep the nouns that name the scene the same as the original prompt: the same character description, the same place, the same light. New nouns invite new objects. If the original clip was lit by a window on the left, say so again, because a prompt that mentions nothing about light leaves the model free to change it.

Step 3: Set resolution and audio, then read the cost

Pick the resolution and decide whether the new footage carries sound. Each video request is priced once from its model, length, resolution and audio setting, then rounded up to a whole credit, and each credit is $0.05. Read the credit cost the page shows before you confirm.

Here is one worked example, priced from the credit table. On Veo 3.1 an 8 second request at 1080p costs 61 credits without audio and 122 credits with it, and at $0.05 a credit the silent version comes to $3.05. Take the figure for a different length or resolution from the page rather than scaling this one, or from the table below.

On Veo 3.1, 1080p costs the same as 720p at 4 and 8 seconds, so pick 1080p.

The live credit table for Veo 3.1 and Kling O3 is on each model page in the model catalogue.

One comparison is worth knowing before you pick a rework instead. Kling O3 charges a source clip at its own rate, 48 credits for a 10 second clip, while Veo 3.1 lists no separate rate for a source clip and charges an extension like a fresh clip of the length you set. The live credit tables are on the model pages and plan prices are on the pricing page, so check there if you are reading this a while after it was written.

Step 4: Generate, then check the first second

Press Generate. When the clip arrives, watch where the new footage begins against the last second of the original: the subject, the framing and the light should carry across. If the new clip opens on a different composition, the prompt described a new shot rather than the next beat, so rewrite it with the same framing words and run it again.

If the continuation is good and you need more seconds still, treat the new clip as a source of its own. Veo 3.1 takes a source clip of up to 8 seconds. Trim the new clip to that length or shorter from the front in the video editor, export it, and extend the exported copy, budgeting for each pass separately.

Keeping the character and scene consistent

A continuation has more to work with when the first clip already holds still on the things you care about. A character who is mid-turn at the last frame gives the model a motion to finish; one who is half out of frame gives it a guess. If you can choose which clip to extend, pick the one whose last frame is a clean, well lit view of the subject.

Reuse the exact character wording from the original prompt, because the words that describe the character are the handle you have on an extension. Age, hair, outfit and the one feature people notice first: write them the same way twice. A prompt that drops the outfit has not asked for the same outfit.

Audio is a separate decision. If the original clip had sound and the extension does not, the change is audible even when the picture carries across, so match the audio setting to the clip you are continuing. If you plan to lay a voice over or music across the whole piece anyway, leave audio off on both and save the difference.

Common problems and fixes

• The clip is too long for Extend. Veo 3.1 takes a source clip of up to 8 seconds. Trim the clip to that length or shorter in the video editor, export it, and extend the exported copy.
• The new clip looks like a different shot. The prompt described a scene instead of the next action. Keep the framing and character words from the original prompt and change only the verb.
• The subject changed clothes or hair. The prompt mentioned nothing about either, so the model chose. Name the outfit and the hair in the prompt, exactly as the original did.
• You need far more than one extension. Plan the piece as several shots instead: generate each one as its own clip, start the next from a frame near the end of the last, and cut them together. How to make AI TikTok videos covers that assembly.
• The result is silent and the original was not. Switch audio on in the request and generate again, and read the new credit cost before you confirm.

For a shot that needs a different model altogether, the AI video generator page lists every model with the clip lengths it offers, and the model catalogue has one page per model with its credit table.