v0.10.0How to use
- Choose your images (you can add several).
- Enter the width and height in pixels, or click a preset button. With "Keep original aspect ratio" on, you only need to enter one value and the other is calculated automatically.
- Choose the output format and click [Resize].
- Check the actual pixel size of each result and download it.
Example
To use a smartphone photo (for example 4032×3024px) in a blog post, click the "Width 1280px" preset and shrink it while keeping the aspect ratio. The result is 1280×960px and the file size drops a lot. If you want it even smaller afterwards, continue with Compress Images.
Reference values for choosing a size
| Use | Reference pixels | Note |
|---|---|---|
| Full-screen monitor (FHD) | 1920×1080 | 16:9 |
| Square post | 1080×1080 | 1:1 |
| A4 print at 150 dpi | 1240×1754 | 210×297mm |
| A4 print at 300 dpi | 2480×3508 | For sharp printing |
Each site and app has its own requirements, and they can change, so check the latest guidance of the service you will upload to first.
Supported formats, limits and privacy
- Input: JPG, PNG and WebP (HEIC only in browsers that support it). Output: JPG, PNG and WebP (only formats your browser supports are shown).
- The output can be at most 12,000px per side. Up to 30 MB per file and up to 30 files at a time.
- With "Keep original aspect ratio" on, the width and height you enter are treated as "the largest size that fits inside". Even if the values do not match the original aspect ratio, the image is not distorted.
- Enlarging an image beyond its original size does not improve quality and may make it look blurry.
- This tool changes the pixel size. It does not change the print resolution (dpi) or the actual printed size (cm). The original EXIF metadata (shooting location, camera information and so on) is not copied into the result. ToolMoru information is recorded automatically in the result file: Software and CreatorTool (ToolMoru) plus the site address (toolmoru.com) in JPG and PNG, and CreatorTool (ToolMoru) plus the site address in WebP. Display-related technical details that the browser adds when saving, such as the color space, may remain.
- All processing happens inside your browser, and nothing is uploaded to a server.
Frequently asked questions
What is the difference between pixels and dpi?
Pixels are the number of dots an image contains (width × height), and dpi is how many dots are printed per inch. The same 1200×1800px image prints at about 10×15 cm at 300 dpi and about 20×30 cm at 150 dpi. For on-screen use, only the pixels matter; for print, work out the number of pixels from the size and dpi you need.
What happens if I do not keep the aspect ratio?
The image is stretched or shrunk to exactly the width and height you enter. If the aspect ratio differs from the original, the image is distorted horizontally or vertically. If you leave one field empty, the original value is used for it.
How do I crop to a square?
Use Crop Images with a 1:1 ratio to cut out the part you want, then resize it here. If you turn off aspect ratio and use a square preset, the image will be distorted.