Common Ratios & Use Cases
| Ratio | Best For |
|---|---|
| 1:1 | Avatars, square stickers |
| 4:3 | Photos, presentation graphics |
| 16:9 | Covers, wide banners |
| 9:16 | Vertical short-video covers |
How to Crop
- Open the image cropping tool.
- Pick a ratio preset or crop freely.
- Drag to adjust the crop area with a live preview.
- Export a high-quality image.
WeChat 9-Grid Slicing
Use the WeChat grid slicer tool to split one large image into 9 equal tiles in a 3×3 grid. Post them to WeChat Moments and they stitch back together into a single long image, with customizable border styles.
- Upload an image.
- Choose whether to add a border.
- Generate and download all 9 images in one click.
Frequently Asked Questions
Choosing a Ratio — and When to Ignore Presets
Presets exist because every platform has a house shape: 1:1 for avatars and square posts, 16:9 for video covers, 9:16 for short-video screens. Matching the destination ratio up front saves you from discovering awkward letterboxing after export. If your target is a printed card or a custom frame, free cropping with a rough target size in mind is the better path.
Composition matters more than the exact numbers. Before locking the crop, ask what the picture is about and let the crop remove everything else: center a face for avatars, leave breathing room above a subject for covers, and keep horizon lines level. Cropping is editing — a tighter frame usually tells a clearer story than the original shot.
Three Pitfalls That Cost You Quality
- Over-cropping small originals. A crop keeps only the pixels inside the frame, so a tight crop of a 800-pixel photo leaves you with a 300-pixel image that looks soft when enlarged. Start from the largest version you have.
- Re-cropping from exports. Every export re-encodes the image. If the first crop was not quite right, go back to the original file and crop again there, not from the saved output.
- Ignoring the destination size. For print, roughly 300 pixels per inch is the comfortable minimum; for a web banner, match the container's displayed size so the browser never scales the image up.
Does cropping reduce image quality?
The tool supports high-quality output with a live preview, so normal cropping won't noticeably reduce quality.
How do I post 9-grid images?
Post all 9 tiles in order to WeChat Moments, and they will display as one complete image.
Which ratio should I use for a profile picture?
Use 1:1. Faces read best square, and every major platform displays avatars in a circle cut from a square — keeping the face centered in the middle third survives that circle crop.
Why does my cropped photo look soft or pixelated?
Almost always because the crop removed too much of a small original. Compare the exported pixel size with where it will be shown; if the export is smaller than the display size, re-crop from a larger source image.
Does cropping change the aspect ratio of my original file?
No — the original file is never modified. Cropping happens on a copy in your browser, and you choose the ratio for the exported result only.
References
- Canvas API — MDN: https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API