Correction, 2026-10-02: the FAQ on chaining keyframes said Merge Videos costs 10 credits "a join" and did not say that its output has no sound. Merge Videos joins 2 to 10 clips for 10 credits a run, and the merged file has no audio track, even when the clips had sound; add audio on the Video Editor timeline or in your own editor.
Correction, 2026-10-01: the end-frame table listed Wan 3.0 Prime and left out Kling O1 Image and Kling O3. On the 8frame canvas, Wan 3.0 Prime takes one start image and no end frame (its end frame is reachable only through the API); Kling O1 Image and O3 do take an end frame. The table and FAQ now say so.
Keyframe animation is a technique where you define the state of a scene at two or more specific moments in time and let the model generate all the frames in between.
In traditional animation, keyframes are the drawings that mark major poses or positions. Everything in between, called in-betweens or tweens, used to be filled in by hand. AI video models automate that entirely. You give them a starting image, an ending image (or a text description of where the scene should end up), and the model synthesizes the transition as a coherent video clip. The result respects both endpoints while producing motion that reads as continuous and physically plausible.
Correction, 2026-09-30: the first version of this page said Kling v3 has a start-and-end-frame mode (on 8frame the end frame works on Kling 2.5 Turbo Pro and 2.1 Pro, not v3), that Veo 3.1 takes text anchors at set timestamps (we can't source that; its keyframe control on 8frame is a first and last frame image), that Veo outputs 4K at 60fps (1080p on 8frame), and described the model internals in detail we can't source. This version lists which models take an end frame and what they cost.
How keyframe animation works
You give the model a first frame and a last frame, and optionally a prompt about how to get from one to the other. The model generates a clip that opens on the first image and lands on the second, with motion in between that should read as continuous: a head turning through plausible positions with consistent light and hair, not a cross-dissolve between two poses.
A prompt still steers the transition: "slow push in, golden hour light warming through the clip" changes pacing and light even when both images are neutral.
When you use keyframe animation
You reach for keyframe control when the default motion from a single image isn't specific enough for what you're building.
Scene transitions. You want a clip to move from an establishing exterior shot to a specific interior. Two keyframes define the start and end states; the model handles the camera move.
Character movement. You have a reference image of a character in a neutral pose and a second reference of them mid-motion. Keyframes lock both states; the interpolation produces the in-between action.
Brand consistency. You need a clip to end on a specific composition, like a product centered on a clean background, even if it starts from a dynamic or busy frame. The end keyframe pins the final composition.
Storyboard-to-video. You have storyboard panels as images. Each panel becomes a keyframe; the model animates the transitions between them, effectively roughing out a full animatic from static frames.
Which models take an end frame on 8frame
| Model | Length with an end frame | Credits |
|---|---|---|
| Veo 3.1 Lite | 8 s | 33 silent, 54 with audio (720p) |
| Veo 3.1 Fast | 8 s | 112 silent, 168 with audio |
| Veo 3.1 | 8 s | 224 silent, 448 with audio (1080p) |
| Kling 2.5 Turbo Pro | 5 or 10 s | 48 / 95 |
| Kling 2.1 Pro | 5 or 10 s | 67 / 133 |
| Kling O1 Image | 5 or 10 s | 73 / 146 |
| Kling O3 | 3 to 15 s | 57 silent, 76 with sound, for 5 s |
| Seedance 2.5 | 4 to 30 s, with a start image and no reference images | 70 (480p) / 157 (720p) for 5 s |
Kling v3, Kling 2.6 Pro, Hailuo H3, Wan 3.0 and several others don't take an end frame on the canvas. Full detail in AI video first and last frame.
Examples to try
A product reveal on Veo 3.1 Lite. First frame: the closed box on a table. Last frame: the product standing next to the open box. Prompt: "hands open the box and lift the product out, slow and steady." 33 credits silent. What to check: hands and packaging through the middle of the clip, where interpolation has the most freedom.
A camera move between two compositions on Kling 2.5 Turbo Pro. First frame: a wide exterior. Last frame: the doorway in medium shot. Prompt: "slow push toward the door." 48 credits for 5 seconds. What to check: that the building's geometry holds as the camera travels.
A dramatic change on Seedance 2.5. First frame: a still product shot. Last frame: the product mid-splash. Prompt: "the product drops into water." 70 credits for 5 seconds at 480p. What to check: that the product keeps its shape and label through the splash.
FAQ
What is keyframe animation in AI video?
Defining the first and last frame of a clip and letting the model generate the motion between them.
Which AI video models support a first and last frame?
On the 8frame canvas: Veo 3.1 (all three tiers, 8 seconds), Kling 2.5 Turbo Pro, 2.1 Pro, O1 Image and O3, and Seedance (with a start image and no reference images).
Can I chain keyframes into a longer sequence?
Yes: use the last frame of one clip as the first frame of the next, then join them (Merge Videos on the canvas joins 2 to 10 clips for 10 credits a run and uses at most 15 seconds of each). The merged file has no sound, even if the clips had audio, so add sound on 8frame's Video Editor timeline or in your own editor. Storyboard panels work well as the keyframes.
Related concepts
- AI video first and last frame: every model, length and price in detail.
- Veo 3 prompt guide: prompt structures for Veo 3.1.
Sources
- 8frame end-frame support, lengths and prices: the 8frame tool registry, 2026-09-30; canvas end-frame support per model (Kling O1 Image, O3, Wan 3.0 Prime): 8frame tool configuration and model compatibility map, read 2026-10-01
Upload a first and a last frame and let the model fill the middle. The 8frame canvas is free and unlimited; generation is paid from $19/month.