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Change Video Resolution and Dimensions

Resize a Video Without Stretching the Picture

Change video resolution by entering a width and height in pixels or scaling by a percentage. With the aspect ratio locked, 1920×1080px becomes 1280×720px when you set the width to 1280px. Choose a preset and scaling method, then check the codec-safe dimensions shown in the preview. Lower resolution can reduce file size; use Compress Video when a size limit is the main requirement.

Cost: Free to use. File size and usage limits apply.

Example: resize Full HD video to HD
Input
1920×1080px video
Setting
Width 1280px · aspect ratio locked
Output
1280×720px video

This changes pixel dimensions. The file size also depends on duration, codec, bitrate and audio.

How to resize a video

  1. Upload one video

    Click Upload a video to resize or drop a file onto the preview. MP4, MOV, M4V, MKV, AVI, WebM, MPEG/MPG and OGV files of up to 200 MB work. If the file manager already holds a video from another tool, one opens automatically; choose another under Uploads without uploading it again.

  2. Choose Pixels or Percent

    Under 1. Size, Pixels takes an exact width and height. Percent scales both sides by the same factor.

  3. Enter the size or click a preset

    The width and height fields start at your video's own size. Type a new width and, with Lock aspect on, the height follows. Or click one of the cards under 2. Presets for a common size.

  4. Check the output size

    The fields take even numbers from 2 to 4096 px. The small line on the Lock aspect card, for example 1280x720px, shows the calculated output size. If it differs from what you wanted, see Lock aspect below.

  5. Pick scaling and quality

    Scaling and Quality sit below the presets. The defaults, lanczos and high, suit most videos.

  6. Resize and download

    Click Resize video. When the job is done, Download saves the file and Continue editing keeps your settings for another try. The result is also added to Uploads, so you can open it in another video tool straight away.

Settings explained

Pixels and Percent
Pixels is for a fixed target such as 1920 x 1080 px. Percent is quicker when you only want the video smaller or larger: 50 % of a 3840 x 2160 px clip is 1920 x 1080 px.
Width and Height
2 to 4096 px each, preset to the size of your video. With Lock aspect on, changing one field fills in the other from your video's proportions. Odd numbers are rounded down to even ones because H.264 and VP9 with standard 4:2:0 colour need even dimensions. The Codec-safe output line shows the rounded result.
Percent slider
10 to 200 %, default 100 %. Both sides are scaled by the same factor, so Lock aspect makes no difference in this mode. Odd results are rounded down to even numbers here too.
Lock aspect
On by default. The video is fitted inside the width x height box without distortion, so one side can come out smaller than the box: a 1920 x 1080 px clip in a 1080 x 1080 px box becomes 1080 x 608 px. Switch it off to get exactly the size you typed; if that shape differs from your video, the picture is stretched or squeezed. The tool never crops and never adds black bars.
Presets
4K 3840 x 2160 px, Full HD 1920 x 1080 px, HD 1280 x 720 px, Story 1080 x 1920 px, Square 1080 x 1080 px and Mobile 640 x 360 px. A preset switches to Pixels and turns Lock aspect off, so you get exactly that size. Pick one with the same shape as your video, or crop first.
Scaling
Decides how the new pixels are calculated. lanczos, the default, uses a windowed-sinc filter; bicubic uses cubic interpolation. bilinear and fast bilinear use simpler interpolation. area averages neighbouring pixels and can suit large reductions such as 4K to 720p. neighbor selects the nearest pixel without smoothing, which can suit pixel art or screen captures enlarged by whole multiples such as 200 %. Compare the contours in your own result before choosing an algorithm.
Quality
Controls the encoder, not the resolution. low, medium, high (default) and best use H.264 CRF 28, 23, 18 and 15; a lower CRF keeps more detail and makes a bigger file. The higher steps also use slower encoder presets, so best takes much longer, and a long 4K clip may not finish within the 15-minute job limit. WebM videos use VP9 at CRF 38, 34, 30 and 26 instead.

Resizing video for Instagram, Reels and TikTok

Instagram Reels and Stories and TikTok use vertical 9:16 video, and 1080 x 1920 px is the usual upload size. Square posts are 1:1. This tool scales the whole frame without cropping or adding bars, so the shape of your clip decides which route works.

Vertical clip that is already 9:16: click Story. A 2160 x 3840 px 4K phone clip becomes 1080 x 1920 px, a quarter of the pixels.

Landscape clip to vertical: resizing alone can't do this cleanly. Story stretches a 16:9 picture to 9:16, and with Lock aspect on a 1920 x 1080 px clip only fits into 1080 x 608 px. Crop the frame to 9:16 first with Crop Video, which leaves about 608 x 1080 px of a 1080p frame, then resize that to 1080 x 1920 px. That is an upscale of roughly 1.8x, so expect a softer picture than footage shot vertically.

Square post: crop to 1:1 first, then click Square.

Formats and limits

Input formats
MP4, MOV, M4V, MKV, AVI, WebM, MPEG/MPG, OGV
Output format
Same container as the upload. MP4, MOV, M4V, MKV and AVI use H.264 video and AAC audio; WebM uses VP9 and Opus at 96 kbps. MPEG/MPG and OGV use video and audio codecs suited to their containers. For MP4 from another format, use Video to MP4.
Output size
2 to 4096 px per side, always even numbers. Larger requests, such as 200 % of a 4K clip, are rejected.
Maximum file size
200 MB per video
Files per job
1
Kept from the source
Frame rate, length, one video track and one audio track. Additional audio tracks are dropped. 10-bit HDR clips, such as those from recent iPhones, are written as 8-bit video, so smooth gradients like a sky can show banding.
Processing
On our servers with FFmpeg. The video is always re-encoded, even at 100 %. A job can run for up to 15 minutes. No AI or third-party service is involved.
Watermark
None
Storage
Uploads and results are deleted automatically after 48 hours for guests and after 30 days for free accounts. Paid plans can keep files longer.

Frequently asked questions

Does it work with vertical phone videos?

Yes. Many phones save portrait video as a landscape frame, for example 1920 x 1080 px, plus a flag that rotates it during playback. The tool reads that flag and treats the clip as the upright video you see: the size fields start at 1080 x 1920 px, Lock aspect and Percent keep the portrait shape, and Story gives a full 1080 x 1920 px result.

Why is the resized video larger than the original?

Resizing always re-encodes, and the default Quality high uses H.264 CRF 18, which keeps a lot of detail. Changing an H.265 (HEVC) recording to H.264 can need more space; MP4 output here uses H.264, while WebM uses VP9. Choose medium or low, pick a smaller size, or run the result through Compress Video with its Target size mode.

Why is the output smaller than the size I entered?

Lock aspect fits the video inside the width x height box instead of filling it. Typing one side keeps the box in your video's shape, so this happens when the box has another shape, for example after you click a preset and switch Lock aspect back on: the HD box of 1280 x 720 px turns a 4:3 clip of 1440 x 1080 px into 960 x 720 px. Type only the width to let the height follow, turn Lock aspect off for the exact size with stretching, or crop to the target shape first.

Does resizing reduce quality?

Downscaling discards pixels; how much that changes the picture depends on its content and the size at which you watch it. Upscaling only interpolates: a 720p clip resized to 1920 x 1080 px has more pixels but no extra detail. Every run is also a new lossy encode, so resize once from the original rather than resizing a resized copy.

Are the sound and the metadata kept?

One audio track is kept and re-encoded for the output container: AAC for MP4, MOV, M4V, MKV and AVI, or Opus for WebM. Tags such as a title or a GPS location are copied into the resized file. If you don't want to share them, Compress Video removes them with its Strip metadata option, which is on by default.