# Image Resizer > Resize images online to exact pixel dimensions. Lock aspect ratio, use social media presets, or enter custom sizes — free, works in your browser. Resize any image by exact pixels, by percentage, or by cropping a selection — all in your browser. Lock the aspect ratio, snap to social-media presets (Instagram, YouTube, TikTok, Facebook, X, LinkedIn), rotate or flip, then export as PNG, JPG, or WebP and see the exact output size. Nothing is uploaded. - **Live tool:** https://www.toolnova.org/image-tools/image-resizer - **Category:** Image Tools (https://www.toolnova.org/image-tools) - **Price:** Free - **Requirements:** Runs in a modern web browser · No signup · No install ## What this tool does - Resize by exact pixels, percentage, or crop selection - Aspect-ratio lock + 8 social-media presets - Rotate 90° and flip horizontal/vertical - Export PNG, JPG or WebP with a quality slider - Live output dimensions and file-size readout - High-quality resampling — 100% client-side ## How to use Image Resizer 1. **Upload an image** — Drag and drop or click to select any photo, screenshot, or graphic. 2. **Choose how to resize** — Pick Pixels for an exact width/height (with optional aspect lock), Scale for a percentage, or Crop to drag a selection box. 3. **Transform & format** — Rotate or flip if needed, then choose PNG, JPG, or WebP output and set the quality. 4. **Apply & download** — Hit Apply to preview, check the output size, then download the resized image. ## Common use cases - Resize a photo to 1080×1080 for an Instagram post - Make a 1280×720 YouTube thumbnail from any image - Scale a large photo down by 50% for faster loading - Crop a headshot or product shot to the exact frame you need - Fit an image under a site or form upload dimension limit ## About ### Resize images to exact dimensions Set a target width and height, or scale by percentage, to resize any image precisely — with the option to keep the aspect ratio so nothing looks stretched. It's ideal for meeting upload limits, fitting layouts, or preparing platform-specific sizes. ### Fast, private, and lossless where it counts Because resizing happens entirely in your browser, there are no uploads, no watermarks, and no waiting on a server. Prepare avatars, thumbnails, and hero images at the correct dimensions in seconds, even for sensitive photos. ## FAQ ### How do I resize an image online for free? Upload your image, enter the desired width and height in pixels (or choose a social media preset), and click Resize. Download the resized image instantly — no software or signup needed. ### What size should I resize images for Instagram? Instagram optimal sizes: Square post = 1080×1080px, Landscape = 1080×566px, Portrait = 1080×1350px, Story/Reel = 1080×1920px. Use the Instagram preset in the tool for automatic sizing. ### How do I resize an image without stretching it? Enable the 'Lock Aspect Ratio' toggle before resizing. This ensures the width and height maintain their proportional relationship, preventing distortion when you change one dimension. ### Can I resize multiple images at once? Yes. The bulk resize feature lets you upload and resize multiple images to the same dimensions simultaneously — useful for batch processing product photos or social media content. ### Will resizing make my image blurry? Resizing down (making smaller) generally maintains sharpness. Resizing up (making larger than original) will introduce some blurriness since the tool needs to create pixel data that doesn't exist. ### What size should I use for a YouTube thumbnail? YouTube thumbnails should be 1280×720px (16:9 aspect ratio) at minimum 72 DPI. File size must be under 2MB. JPG format works best for thumbnails. ### Can I resize without stretching? Yes — lock the aspect ratio and the tool scales width and height together so the image keeps its proportions. --- ToolNova — free, privacy-first browser tools. Most tools process data locally on your device. See https://www.toolnova.org/llms.txt for the full directory.