AI Video Studio
FreeVideoGenerator.io · Free online video resizer
Free Online Video Resizer
Resize and crop videos for any platform — Instagram Reels (9:16), YouTube (16:9), TikTok (9:16), Twitter / X (16:9 and other common sizes), and more. Set custom dimensions or choose from platform presets. Everything runs locally in your browser — your file is not uploaded.
Resize Video Now — It's Free100% Free
Private · on your device
Works in Browser
Platform Presets
Browser editor
Drop a video to resize
or click to browse
Input: MP4, MOV, WebM, MKV, and other formats your browser can read
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Discover our AI-powered video and image tools.
How It Works
Three steps. Any dimension.
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1. Upload Your Video
Drop any common video file (MP4, MOV, WebM, MKV, and more) onto the page. Your file stays on your device for the whole process — nothing is sent to our servers.
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2. Choose Your Dimensions
Select a platform preset (Instagram, TikTok, YouTube, X / Twitter, LinkedIn) or enter custom width and height. When aspect ratios differ, pick crop-to-fill to center the frame, or fit-with-letterbox to keep the entire picture with black bars — no account required.
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3. Download Your Resized Video
Click to export. Processing runs in your browser with WebCodecs (H.264) for broad compatibility. Free exports include a small branded watermark; paid users download without it.
Platform Presets & Sizes
Use these as a quick reference. Each is available as a one-click target in the tool (plus custom size).
Instagram Reels & Stories — 9:16 (1080×1920)
Portrait format for full-screen mobile viewing. Ideal for Reels, Stories, and TikTok. When your source is landscape, “crop to fill” centers the frame; “fit with letterbox” shows the full image with padding.
Instagram Feed — 4:5 (1080×1350)
A strong choice for feed posts that use more vertical space than square — often better visibility in the stream without being as tall as 9:16.
Instagram Square — 1:1 (1080×1080)
Classic square for the grid — product shots, portraits, and content that should look good in a uniform tile layout.
YouTube — 16:9 (1920×1080)
Standard widescreen for YouTube and many landscape social placements (including some LinkedIn and Facebook use cases).
TikTok — 9:16 (1080×1920)
Full-screen vertical video for TikTok. Same 9:16 size as Reels/Stories, so one export can cover multiple short-form apps.
X / Twitter — 16:9 (1280×720)
A common landscape size for video posts on X. The platform also supports other aspect ratios; match your campaign or organic format here.
LinkedIn — 16:9 (1920×1080)
Professional landscape for native video in the feed and many ad formats.
Custom dimensions
Enter any width and height in range for kiosks, digital signage, special ad units, or non-standard deliverables — alongside our presets for social.
Quick reference: presets in the tool
Same dimensions as the preset buttons in the editor — use it to compare at a glance.
| Preset | Resolution | Aspect |
|---|---|---|
| Instagram Reels (9:16) | 1080×1920 | 9:16 |
| TikTok (9:16) | 1080×1920 | 9:16 |
| YouTube Shorts (9:16) | 1080×1920 | 9:16 |
| Instagram Portrait (4:5) | 1080×1350 | 4:5 |
| Instagram Square (1:1) | 1080×1080 | 1:1 |
| YouTube (16:9) | 1920×1080 | 16:9 |
| LinkedIn (16:9) | 1920×1080 | 16:9 |
| X / Twitter (16:9) | 1280×720 | 16:9 |
Platform recommendations change — confirm current specs in each app’s help center before publishing.
What Is a Video Resizer?
A video resizer changes the dimensions, aspect ratio, or resolution of a video to match a platform, device, or creative brief. What looks right on YouTube may letterbox on Instagram, and a landscape clip won’t fill a 9:16 Shorts or TikTok screen without scaling or padding.
Scaling
Scaling changes width and height, usually keeping the original aspect ratio. Scaling down reduces file size and matches platform limits. Scaling up can’t add real detail; very large upscales can look softer, so 1080p is often the sweet spot for social.
Cropping
Cropping removes edge pixels to match a new aspect ratio — for example, turning 16:9 into 9:16 by taking the middle. Our crop-to-fill mode scales to cover the target box, then crops overflow (visually, a centered result for most shots).
Padding (letterboxing & pillarboxing)
When you don’t want to lose the edges, fit-with-letterbox scales the image to sit inside the target and adds black bars on the top/bottom or sides. The whole original frame remains visible.
This resizer lets you pick crop-to-fill or fit-with-letterbox and outputs MP4 in your browser — so you can combine scaling with either crop or padding in one pass.
Why Aspect Ratio Matters for Social Media
The aspect ratio controls how your video looks in the feed. The wrong ratio can add black bars, awkward crops, or a smaller footprint than competitors’ posts.
Most social viewing is on phones. Vertical 9:16 fills the screen; landscape in a mobile feed can look small or padded. That difference affects attention and watch time.
On networks like Instagram, taller feed formats (4:5, 9:16) can occupy more scroll space than square or wide posts — more space often means more chances to be noticed when the feed is busy.
Each network has preferred default displays. Natively-sized vertical for TikTok or Reels tends to look intentional; a mismatched upload may get letterboxed or re-cropped by the app. Re-exporting to the right ratio before upload keeps you in control.
Many creators shoot 9:16 first, then export 16:9 for YouTube and 1:1 for feed grids — a practical pipeline when one shoot feeds multiple channels.
Resolution Guide
Match resolution to your delivery target. Here’s a simple reference (not a limit of the tool; custom sizes are supported).
| Label | Dimensions | Best for |
|---|---|---|
| 4K UHD | 3840×2160 | YouTube, mastering / archive |
| 1080p Full HD | 1920×1080 (16:9) or 1080×1920 (9:16) | YouTube, most social, sharp on current phones |
| 720p HD | 1280×720 | Lighter files, many social placements |
| 480p SD | 854×480 | Smaller files, limited bandwidth |
| 360p | 640×360 | Preview-sized or very small exports |
For most social use, 1080p height (1080px on the long side) is a practical balance: sharp on devices while keeping sizes reasonable. Many platforms recompress on upload regardless.
Key Features
Platform Presets
One-click targets for Reels, Shorts, YouTube, square 1:1, 4:5 feed, X/Twitter, LinkedIn, and more — each sets width, height, and aspect for you.
Crop or padding
When ratios don’t match, choose crop-to-fill (no letterboxing) or fit-with-letterbox (keep the full frame with bars).
High-quality re-encode
Resizing uses a full re-encode path in the browser (WebCodecs) so the output is tuned for the target size — not a rough stretch in the player alone.
Custom width & height
Set exact pixel dimensions for non-standard or internal deliverables, not just social presets.
No upload required
The pipeline runs in your tab; files are not sent to us for processing.
Flexible export
Download a watermarked MP4 for free, or upgrade to any paid plan for clean exports without the site watermark.
Frequently Asked Questions
What aspect ratios are supported?
Common presets include 16:9, 9:16, 1:1, 4:5, and 16:9 at 1280×720 for X. You can also set any custom width and height within the tool’s allowed range to create other ratios (e.g. 4:3).
Will resizing reduce video quality?
Scaling down always involves recompression; we encode with standard H.264 in-browser for a predictable result. Cropping in crop-to-fill doesn’t add blur — it removes edges after scaling. Scaling up can’t add real detail; avoid heavy upscales when possible.
What’s the best aspect ratio for Instagram?
It depends on placement: 9:16 for Reels/Stories, 1:1 for a classic feed grid, 4:5 for more vertical feed real estate, and 16:9 when you need widescreen. Match the placement you’re posting to.
Can I resize a video without cropping?
Yes. If the target aspect matches your source, the frame can scale without losing edges. If ratios differ, use fit-with-letterbox to avoid cropping (black bars may appear) instead of crop-to-fill.
What’s the maximum resolution I can export?
The tool supports large dimensions in principle, but practical limits are your device RAM, clip length, and browser stability. Very high resolutions and long 4K files take more time; close other heavy tabs and prefer desktop Chrome/Edge for difficult jobs.
What formats are supported?
You can import most formats the browser and our reader can demux (commonly MP4, MOV, WebM, MKV). Output is MP4 (H.264) for wide compatibility on phones, editors, and platforms.
Can I resize multiple videos at once?
This page processes one file per export. Run another pass for additional clips, or use dedicated batch tools outside the browser for large batches.
Do I need an account?
No. There’s no signup, login, or email required to use the resizer.
Related Tools on FreeVideoGenerator.io
- Video CompressorReduce file size in the browser for easier sharing
- Video ConverterConvert between MP4, WebM, MOV, MKV, and more
- Video TrimmerCut and trim videos with a simple in-browser flow
- Video MergerCombine multiple clips into one video
- Remove Audio from VideoStrip audio tracks when you need a silent file
- GIF MakerTurn short clips into animated GIFs
Why FreeVideoGenerator.io?
You shouldn’t need a cloud upload to match TikTok, Instagram, or YouTube dimensions. This resizer runs in your browser: your file stays on your device. Free downloads include a small branded watermark; upgrade to any paid plan anytime to export without it.
We combine one-click social presets with honest fit modes — scale and crop, or scale and pad — so you can ship platform-ready MP4s from a single pass. For new footage generated with AI, you can also start from our free video generator and export in the sizes you need.
Try the AI video generator
Create platform-ready videos with AI
Generate new clips in popular aspect ratios from text or images — then refine size here if needed.
Try the AI video generator →