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Social Aspect Ratio Resizer
TikTok & ReelsResize video for TikTok, Reels, Shorts (9:16), Instagram (1:1), YouTube (16:9) free
100% Client-Side WebAssembly
Fast
No File Size Limits
Step-by-Step Instructions
How to use Social Aspect Ratio Resizer
Follow these 3 quick steps to process your media privately in your browser.
01
Upload Video
Select your landscape, portrait, or square video from your device.
02
Pick Aspect Ratio
Choose 9:16 (TikTok/Reels), 1:1 (Instagram), or 16:9 (YouTube) and select Crop or Pad mode.
03
Export & Post
Download your perfectly resized video ready to upload to social media.
100% Client-Side Computing
Why use Social Aspect Ratio Resizer on VideoReduce.com?
Zero server uploads, infinite privacy, and native WebAssembly hardware acceleration.
Social Media Presets
One-click presets for 9:16 (TikTok/Reels/Shorts), 1:1 (Instagram), and 16:9 (YouTube/Widescreen).
Crop vs Letterbox Padding
Choose full-screen center-crop or elegant black letterbox padding to keep your entire video in frame.
Crisp 1080p HD Output
All resized videos are exported at standard 1080p high-definition resolution.
100% Private & Free
Resize videos entirely in your browser. No upload, no watermarks, no file size limits.
Platform Solution Hubs & Presets
One-click optimized presets for specific social media and communication platforms.
WhatsApp 16MB Fix
Compress Video for WhatsApp
Reduce large smartphone videos under WhatsApp's 16MB limit without blurry compression
Discord 25MB Fix
Compress Video for Discord
Reduce gaming clips and memes for Discord with instant inline web embed playback
Email 25MB Cap
Compress Video for Email
Shrink gigabyte videos down to email-friendly attachments in seconds without third-party links
UHD Downscale
4K to 1080p Downscaler
Reduce massive 4K file sizes by up to 75% while keeping crystal-clear 1080p sharpness
Instagram 2026 Ready
Compress Video for Instagram Reels
Optimize vertical 9:16 videos for Instagram Reels and Stories to stop Instagram's blurry upload compression
TikTok 2026 Specs
Compress Video for TikTok
Optimize vertical TikTok clips for maximum algorithm clarity and fast viral playback
Shorts 60s Max Bitrate
Compress Video for YouTube Shorts
Fine-tune vertical videos for YouTube Shorts with optimal bitrate and fast VP9/AV1 YouTube transcoding
Slack Workspace Fix
Compress Video for Slack
Shrink screen recordings and bug demos for Slack workspace channels with instant inline player playback
X Feed Optimization
Compress Video for Twitter / X
Compress and format videos for Twitter / X feeds to maximize engagement with instant muted autoplay
PPT Presentation Fix
Compress Video for PowerPoint
Reduce video size inside Microsoft PowerPoint presentations to stop slide freezing and prevent file bloat
Meeting Archive
Compress Zoom Recording
Shrink multi-hour Zoom, Teams, and Google Meet video recordings by up to 90% for easy sharing and archiving
10MB Strict Limit
Compress Video Under 10MB
Shrink any video down to exactly under 10MB for strict job portals, government forms, and email systems
25MB Universal Cap
Compress Video Under 25MB
Reduce video files under 25MB for universal compatibility across Gmail, Discord, Outlook, and web forms
50MB Portal Standard
Compress Video Under 50MB
Reduce large videos under 50MB for social media uploads, LMS submissions, and web portals
100MB LMS Standard
Compress Video Under 100MB
Compress student video assignments, university presentations, and course modules under 100MB
Apple 4K HDR Fix
Compress iPhone Video
Reduce heavy iPhone 4K ProRes and HEVC MOV video sizes by up to 85% for effortless sharing with Android and PC
Related Engineering & Privacy Guides
In-depth research by the VideoReduce Media Lab.
Compression
How to Reduce Video File Size Without Losing Quality (Complete 2026 Guide)
Discover how to reduce video file size online for free without losing quality. Complete guide on reducing video storage size on iPhone, mobile phones, and PC, plus Discord 8MB/10MB compressor settings.
Privacy & SecurityWhy Traditional Online Video Converters Are a Privacy Nightmare (And How WebAssembly Fixes It)
Every time you upload a smartphone video to a cloud converter, you transmit embedded GPS location tags, camera serial numbers, and unencrypted footage to remote servers. Learn how client-side WebAssembly solves this privacy crisis.
Platform GuidesHow to Compress Large Videos for WhatsApp, Discord, and Email (Exact Workarounds)
A practical cheatsheet for sending large HD video clips over WhatsApp (16MB limit), Discord (8MB/25MB limits), and Gmail/Outlook (25MB attachment cap) with one-click presets on VideoReduce.com.
User Community Reviews & Recommendations
Rate Social Aspect Ratio Resizer
Your honest feedback and recommendations directly shape our next updates.
4.9out of 5
1,280+ Verified User Ratings
Frequently Asked Questions
Everything you need to know about Social Aspect Ratio Resizer and local WebAssembly processing.
How to resize a video for TikTok or Instagram Reels?
Upload your landscape video, select the 9:16 aspect ratio preset, choose Center Crop or Letterbox Pad mode, and click Export. You'll get a vertical video perfectly sized for TikTok, Instagram Reels, and YouTube Shorts.
What is the difference between crop and letterbox?
Crop fills the entire frame by cutting the sides of your video (full-screen, but loses some edges). Letterbox adds black bars to fit the entire video within the new aspect ratio (keeps everything, but has borders).
Can I convert a YouTube video to vertical for TikTok?
Yes! Upload your 16:9 YouTube-format video, select 9:16, and the tool will center-crop or pad it for perfect TikTok/Reels vertical format.
What resolution are the output videos?
All videos are exported at standard 1080p HD (1920x1080 for 16:9, 1080x1920 for 9:16, 1080x1080 for 1:1) for crisp social media quality.
Does this work with iPhone MOV files?
Yes! Upload iPhone QuickTime .MOV recordings and resize them to any aspect ratio. Works directly in Safari and Chrome on iOS.