Turn a 16:9 master into 9:16, 4:5 and 1:1 ad versions, or a vertical video into 16:9, without opening After Effects. Frame the shot by hand, animate the crop with keyframes and export an MP4 encoded in your browser. Nothing is uploaded.
Drop a video master
MP4, MOV or WebM that this browser can play. The file is read on your machine and never uploaded.
Choose video
Output size
Source
Drag the window, or the picture on the right, to frame the shot. Arrow keys move it in small steps, Shift with an arrow in large ones.
Output
0:00.00 / 0:00.00
Fill the frame
Keyframes
No keyframes: one framing for the whole clip. Add a keyframe to animate it, then every change at a new time adds another.
Export
Social cutdowns Pro
Every size keeps its own framing, keyframes and fill. Press Frame next to a ratio to set it up above, tick the ones you need, and export them all in one run: each file is checked against the placements that use its ratio and the set arrives as one ZIP with a manifest. One ratio at a time stays free with Export video.
Each check reads the exported file with the Ad Spec Checker rules. Open a file there to see every rule for every placement.
How Video Reframe works
Drop a master and pick a target size. The source sits on the left with the crop window drawn over it, the finished frame on the right with the safe zone of the platform you choose. Drag either one to frame the shot, zoom to push in, then press Export video. The file is read from your disk in small chunks, every frame is drawn at the output size and encoded with WebCodecs, the video encoder built into your browser, so a long 4K master never has to fit in memory and nothing is sent to a server.
Three ways to fill a new ratio
Crop to fill cuts the new ratio out of the master. A 1920 × 1080 master cropped to 1080 × 1920 keeps a slice 607.5 px wide, 31.6% of the original width, so it suits shots where the action stays in one part of the frame. Keyframes let the slice follow a moving subject.
Fit, blurred background keeps the whole master visible, scaled to the width of the vertical frame, over an enlarged and blurred copy of itself. The picture fills 607.5 of the 1920 px height, so it is the safe choice for packshots, supers and end cards that must stay whole.
Fit, solid colour does the same on a flat brand colour. Slide the picture to the top or bottom to leave a clean block for a headline or a call to action you add later in your editor.
Keyframes for moving subjects
Press Add keyframe and the framing becomes animated: from then on every change at a new time adds a keyframe, the way the stopwatch works in After Effects. Between keyframes the window eases out of one position and into the next. Switch the easing to Linear for a constant pan, or to Hold to cut between framings on the keyframe. Zoom is keyframed together with the position, so a slow push in is two keyframes.
Social cutdowns from one master
Every output size keeps its own framing. Frame the 9:16 version with a crop that follows the subject, switch to 4:5 and fit the packshot on a blurred background, switch to 1:1 and push in, and each one remembers its own keyframes, zoom and fill. When the master has a ratio of its own, such as 2.39:1, it gets a Source size too. With AdCheckLab Pro, tick the sizes you need and export them in one run: they are encoded one after another on this machine, each file is read back with the Ad Spec Checker rules against the placements that use its ratio (Reels, Stories, TikTok In-Feed, Shorts, Snapchat and Pinterest Idea ads for 9:16, the Facebook and Instagram feeds, LinkedIn video and standard Pinterest pins for 4:5 and 1:1, YouTube in stream and LinkedIn video for 16:9), and the set arrives as one ZIP with a manifest listing every file, its framing and its verdict. A single size at a time stays free.
Safe zones on the output
The output preview shows what each platform's interface covers. The overlays are the same masks as on the Safe Zone Templates page, drawn from the official specs and templates of Meta, TikTok, Google, Snap and Pinterest and from EBU R95 for broadcast, so a super placed in the clear area here stays clear of the buttons and captions there. For a frame by frame check of the finished file, with automatic detection of text near the edges, open it in the Safe Zone Checker.
Export settings
The MP4 carries H.264 video and AAC audio, the pairing every major ad platform lists first. The bitrate starts from YouTube's recommended upload rates: 8 Mbps for 1080p at up to 30 fps and 12 Mbps above that, scaled by pixel count for other sizes, which puts a 30 second 1080 × 1920 ad at about 30 MB. Audio that is already AAC is copied untouched. When the browser cannot encode H.264 the export falls back to WebM with VP9 and Opus, and the page tells you before you start. Run the result through the Ad Spec Checker to confirm duration, file size, frame rate and bitrate against every placement, and read the guide to social media video aspect ratios for which ratio each placement prefers.
Questions about Video Reframe
No. The video is decoded, reframed and encoded inside this browser tab. The only thing fetched when you export is the open source encoding library, Mediabunny, under 200 KB compressed, loaded from jsDelivr and checked against a pinned hash before it runs.
Video export needs the WebCodecs API, which current versions of Chrome, Edge, Firefox and Safari provide on desktop. Older browsers and some mobile browsers lack it. Save frame as JPG still works there.
Yes. AAC audio is copied without encoding it again. Other audio, such as PCM in a MOV, is encoded to AAC for MP4 or Opus for WebM. If the browser can encode neither, the video is exported without sound and the page warns you first.
1080 × 1920 covers Reels, Stories, TikTok and Shorts, 1080 × 1350 the 4:5 feed, 1080 × 1080 the square feed and 1920 × 1080 in stream video. Meta recommends 1440 × 2560 for Stories and Reels ads, so pick Custom for that one. The Meta, TikTok and YouTube spec guides list every placement.
Yes, with Pro. Frame each size once, tick the ones you need under Social cutdowns and press Export. The files are encoded one after another, checked against the placements that use each ratio and delivered as one ZIP with a manifest. Exporting one size at a time with Export video is free.
Yes. Move the playhead to the frame you want and press Save frame as JPG. The still is rendered at the full output size with the same crop, zoom and background as the video, without the safe zone overlay.
