• English
  • Deutsch
  • Español
  • 中文简体
  • 中文繁體
  • 日本語
  • 한국어
  • ไทย
  • Tiếng Việt
ArtPlayer logoArtplayer
ArtPlayer logoArtplayer
ArtPlayer Editor
Artplayer AI
Subtitle EditorFree Video Tools

Video Upscaler
X GIF Downloader
Facebook Video Downloader
Loop Audio
Change Volume

Video Screenshot
Remove Watermark
Trim Video
Compress Video
Pixelate Video
Merge Video
Video Stabilizer
Blur Video
Reverse Video
Split Video
Frame Interpolation
Fade Video
Flip Video
Image to Video
Add Audio
HLS to MP4
Remove Metadata
Countdown Video
Blur Background
Speed Video
Rotate Video
Resize Video
Adjust Video
Normalize Video
Split Screen Video
Video to GIF
Edit Metadata
Add Subtitles
Add Text
Boomerang Video
Crop Video
Remux Video
Inspect Metadata
Loop Video
Scene Splitter
M3U8 Downloader
Video Understanding
Extract Thumbnail
Video Converter
Green Screen
Pixelate Face
Mute Video
Add Watermark
Image Slideshow
Blur Face
Stop Motion Effect
Filter Video
GIF to MP4
PDF to Video
Thumbnail Sprites
Add Photo
Landscape to Portrait
Extract Tracks
Animated Circles
Add Intro Image
Video to HLS
Solid Color Video
Video Overlay
Freeze Frame
Video to Text
Sync Audio and Video

X Video Downloader
TikTok Video Downloader
Instagram Video Downloader
Tenor GIF Downloader
Threads Video Downloader
Reddit Video Downloader
Pinterest Video Downloader
Pinterest GIF Downloader
GIPHY GIF Downloader
Imgur Video Downloader
Imgur GIF Downloader

Add Cover Art
Speed Audio
Join Audio
Trim Audio
Vocal Separation
Filter Audio
Extract Audio
Measure Loudness
Equalize Audio
Split Audio
Change Volume
Normalize Audio
Add Reverb
Remove Silence
Reduce Noise
Audio Visualizer
Fade Audio
Convert Audio
Change Pitch
Reverse Audio
Text to Speech
Compress Audio
Detect BPM
Speech to Text

Image Upscaler
GIF Upscaler
AI Image Expander
Remove Watermark
Old Photo Restore
Depth Map
Blind Watermark
GIF Optimizer
Image to Prompt
Background Changer
Remove Background
Remove Object
Remove AI Labels
AI Image to GIF

Screen Recorder
Voice Recorder
Camera Recorder
GitHubDocsAbout

MP4 dimensions

Resize MP4 Online

Change an MP4 frame size or aspect ratio for a screen, presentation, or publishing workflow without uploading the source.

Resize an MP4 Crop video first

Resize an MP4 without confusing dimensions and file size

Video dimensions describe the width and height of each frame. They affect presentation and can influence file size, but resizing is different from compression.

01

Choose dimensions for the destination

Start with the screen or placement where the MP4 will be used. Landscape suits widescreen players, portrait fits vertical layouts, and square works for balanced social compositions. Keeping the original ratio avoids distortion when no destination-specific frame is required.

  • Use landscape for widescreen players and presentations.
  • Choose portrait or square only when the destination needs that shape.
  • Keep the original ratio when preserving the full composition matters.
02

Distinguish resizing from compression

Reducing resolution can lower the amount of visual data in an MP4, but it does not guarantee a particular file size. Duration, frame rate, motion, codec, and bitrate also matter. Use the video compressor afterward when an upload limit is the primary goal.

  • Check faces, captions, and interface text after downscaling.
  • Use Crop Video first when the new ratio needs a different composition.
  • Use Compress Video when the final byte size matters more than dimensions.
Artplayer AI

Take your next edit further with AI.

Enhance videos, restore photos or separate audio with Artplayer AI.

Explore Artplayer AI

How it works

Three steps to finish the browser workflow.

  1. 1

    Choose an MP4

    Open Resize Video and select the MP4 you want to resize.

  2. 2

    Set the output shape

    Choose landscape, portrait, square, or keep the original aspect ratio.

  3. 3

    Export the resized MP4

    Preview the frame, process it locally, and download the new MP4.

Everything you need

Core details about privacy, browser support, output, and practical limits before you start.

Landscape, portrait, square, and original-ratio output

Choose dimensions based on the final player or publishing destination.

Local browser MP4 processing

The MP4 stays on your device while the browser creates the resized result.

Watermark-free export

Use compression separately when you need to meet a file-size limit.

Frequently asked questions

Quick answers about privacy, output, and practical limits before you start.

Can I change an MP4 resolution online?

Yes. The linked resizer changes the video dimensions and exports a new MP4 in your browser.

Does resizing make every MP4 smaller?

Lower resolution can reduce output size, but duration, motion, frame rate, and encoding settings also affect the result.

Is the MP4 uploaded?

No. The resize workflow runs locally in your browser for supported files.

Related tools

Continue editing with nearby ArtPlayer tools that work with the same browser-first workflow.

Resize Video
Resize Video
Change video dimensions for landscape, portrait, square, or original-ratio outputs.
Crop Video
Crop Video
Adjust framing with crop ratios and a visual crop guide for the final export.
Compress Video
Compress Video
Reduce video file size with simple presets and local browser processing.
View all tools
ArtPlayer logoArtplayer

Free browser media tools for editing, converting, recording, and preparing video, audio, subtitles, and AI-assisted results.

Email us: [email protected] Buy Me a Coffee

Video tools

Change VolumeVideo ScreenshotRemove WatermarkTrim VideoCompress VideoPixelate VideoMerge VideoVideo StabilizerBlur VideoReverse Video

Audio tools

Loop AudioAdd Cover ArtSpeed AudioJoin AudioTrim AudioVocal SeparationFilter AudioExtract AudioMeasure LoudnessEqualize Audio

Image tools

Image UpscalerGIF UpscalerAI Image ExpanderRemove WatermarkOld Photo RestoreDepth MapBlind WatermarkGIF OptimizerImage to PromptBackground Changer

Downloaders

X GIF DownloaderFacebook Video DownloaderX Video DownloaderTikTok Video DownloaderInstagram Video DownloaderTenor GIF DownloaderThreads Video DownloaderReddit Video DownloaderPinterest Video DownloaderPinterest GIF Downloader

Site

Free Video ToolsTool usage statisticsArtPlayer EditorSubtitle EditorBlogAboutFAQDocs
© 2026 ArtPlayer. All rights reserved.
PrivacyTermsCookiesAcceptable UseCopyright

Essential cookies keep ArtPlayer working. You choose whether to allow optional cookies. Cookie Policy