Image Resizer
Change the pixel size of a picture without leaving the page — fit it in a box, cover one, or scale it by a percentage.
Results
What this tool does
Most of the reasons to resize a photo are boring and constant: an upload form that refuses anything over 2000 pixels, a forum avatar, a document that will not accept a 12-megapixel camera file. This page does that work in your own browser. Choose an image, say how big you want it, and the result appears with a download button. The picture is never sent anywhere; it is read, redrawn and handed straight back.
Formula
the target size comes from the chosen mode: fit uses the smaller of the two factors, cover uses the larger, percentage multiplies both sides by the same number
Variables
| Symbol | Meaning | Unit |
|---|---|---|
source_w | Original width | — |
source_h | Original height | — |
mode | How to fit | — |
target_w | Width you want | px |
target_h | Height you want | px |
percent | Percentage | % |
format | Save as | — |
quality | Quality | % |
OUT | New size | — |
OW | New width | px |
OH | New height | px |
SC | Size after resizing | % |
MP | Megapixels | — |
AR | Shape (width to height) | — |
SR | Shape of the original | — |
Worked example
- Original width4032
- Original height3024
- How to fitfit
- Width you want1600 px
- Height you want1600 px
- Percentage50 %
- Save asimage/jpeg
- Quality85 %
- New size1600 x 1200
- New width1600 px
- New height1200 px
- Size after resizing39.7 %
- Megapixels1.92
- Shape (width to height)4:3
- Shape of the original4:3
Limitations
- The calculation runs entirely in your browser. The values you type are never sent to a server.
Frequently asked questions
Does my photo get uploaded anywhere?
No. The file is read by your own browser, redrawn on a canvas and handed straight back to you as a download. Nothing leaves the machine, which is also why the page keeps working with the network switched off.
What is the difference between fitting and covering?
Fitting shrinks the picture until the whole of it is inside the box you asked for, so one side usually comes out smaller than the number you typed. Covering shrinks it until the box is completely filled, so one side comes out larger and would be trimmed. Neither one stretches the picture out of shape.