Resize GIF Online — Free, No Upload Required
Change GIF dimensions while preserving animation quality. Bilinear interpolation for smooth scaling. All processing in your browser — no files leave your device.
Drop a file here
or click to browse · GIF files up to 50 MB
Paste from clipboard also works
How to Resize a GIF
- Drop a GIF file onto the tool above, or click to browse. The tool reads the file dimensions automatically.
- Enter the desired width and height. Aspect ratio lock is enabled by default — changing one dimension adjusts the other proportionally.
- Click Resize. The tool decodes every frame, applies bilinear interpolation to scale each frame, re-quantizes colors, and encodes the output GIF.
- Download the resized GIF. The output panel shows the new dimensions, file size comparison, and quality metrics.
Why Resize GIF Files
GIF file size scales with pixel count. A 640×480 GIF contains 307,200 pixels per frame. Reducing to 320×240 cuts that to 76,800 pixels — a 75% reduction in pixel data per frame. For animated GIFs with many frames, this translates to significant file size savings.
Common reasons to resize GIFs include meeting platform upload limits (Discord 8 MB, Twitter 15 MB), reducing page load times when embedding GIFs in web content, and fitting GIFs into specific layout dimensions for presentations or documentation.
Resize Methods
Bilinear Interpolation
This tool uses bilinear interpolation for resizing. For each pixel in the output image, bilinear interpolation samples the four nearest pixels in the source image and computes a weighted average based on distance. This produces smooth results for both upscaling and downscaling, avoiding the blocky artifacts of nearest-neighbor scaling.
After resizing, the RGBA pixel data is re-quantized to a GIF-compatible palette (up to 256 colors) and optionally dithered using Floyd-Steinberg error diffusion. Frame optimization then identifies unchanged regions between frames to minimize the encoded data.
Aspect Ratio
Maintaining the original aspect ratio prevents distortion. When the aspect ratio lock is enabled, changing the width automatically calculates the corresponding height, and vice versa. Unlock the aspect ratio to set width and height independently — useful when you need to fit a GIF into a specific rectangular area.
GIF Dimension Limits by Platform
- Discord: No specific dimension limit, but 8 MB file size limit (50 MB with Nitro).
- Twitter/X: Maximum 1280×1080 pixels. GIFs larger than this are automatically resized.
- Slack: No specific dimension limit. Large GIFs may display at reduced size in the message view.
- Reddit: Maximum 20 MB. No specific dimension limit, but very large GIFs may not display inline.
- GitHub: GIFs in README files display at the container width. Recommended maximum 800px wide.
- Email: Most email clients display images at the container width (typically 600px). Larger GIFs are scaled down.
Resize and File Size
The relationship between dimensions and file size is approximately quadratic. Halving both width and height reduces pixel count by 75%, which typically results in a 50-75% file size reduction. The exact reduction depends on content complexity — GIFs with large uniform areas compress more efficiently at any size.
For maximum file size reduction, combine resizing with compression. Resize the GIF to your target dimensions first, then use the GIF Compressor to further reduce the color palette and optimize frames.
Frequently Asked Questions
This tool uses bilinear interpolation to resize each frame, which produces smooth results for both upscaling and downscaling. After resizing, color quantization and optional dithering reconstruct the GIF palette. Using the Balanced quality tier with dithering enabled produces the best visual results.
Yes. The aspect ratio lock is enabled by default. When you change the width, the height adjusts automatically to maintain the original proportions, and vice versa. You can unlock the aspect ratio to set width and height independently.
Reducing dimensions typically reduces file size because fewer pixels need to be encoded per frame. A GIF resized from 640×480 to 320×240 contains one quarter of the pixel data, which generally results in a 50-75% file size reduction depending on content complexity.
This tool accepts GIF files up to 50 MB with up to 1000 frames. Output dimensions are limited to 2048×2048 pixels. Processing occurs entirely in your browser.
No. All processing occurs in your browser using Web Workers. Your files are never transmitted to any server. The tool works offline after the first visit.