图片元数据与尺寸查看器
查看图片尺寸、宽高比、像素量与打印尺寸，同时读取包含相机、镜头和 GPS 的 EXIF 信息。
What is EXIF
EXIF is the metadata block that cameras write into photos. It records the camera model, lens, aperture, shutter speed, ISO, GPS coordinates and the capture date. It is genuinely useful — and also a genuine privacy risk.
The privacy problem
A photo taken at home often contains the exact GPS coordinates of your house, the serial number of your camera and a timestamp. If you upload that to a social network without stripping metadata, you have published your location.
Before publishing a photo from home, check it here. If there is a GPS field, strip it first:
# Linux, with ImageMagick
exiftool -gps:all= photo.jpg
# macOS, with exiftool
exiftool -all= photo.jpgMost phones also have a "location" toggle in the camera settings. Turning it off stops the problem at the source.
Print dimensions
The useful rule is pixels divided by DPI. At 300 DPI, which is the standard for high-quality print:
| Resolution | Print size |
|---|---|
| 1920 x 1080 | 6.4 x 3.6 inches |
| 3000 x 2000 | 10 x 6.7 inches |
| 4000 x 3000 | 13.3 x 10 inches |
| 6000 x 4000 | 20 x 13.3 inches |
For screen use, 72–96 DPI is what matters. A 1920x1080 image at 96 DPI displays at exactly 20 x 11.25 inches, which is a 1080p monitor at 1920x1080.
Aspect ratios
| Ratio | Common use |
|---|---|
| 16:9 | Video, widescreen displays |
| 4:3 | Camera sensors, older displays |
| 3:2 | DSLR full-frame, photography |
| 1:1 | Social media squares, Instagram |
| 9:16 | Vertical video, stories and reels |
| 21:9 | Ultrawide monitors |
Privacy note
Everything here runs in your browser using the FileReader and EXIF parsing APIs. Your photo is never uploaded, so you can safely inspect a picture from a client without sending it anywhere.
常见问题
Is my photo uploaded anywhere?
No. The file is read locally in your browser and never transmitted. This matters when you are checking a photo before sending it to someone.
Does it remove the metadata?
No, it only reads it. To strip metadata use a dedicated tool such as exiftool, or export a copy from your image editor with the metadata option turned off.
How do I know if a photo has GPS data?
Look for the GPS fields in the metadata output. If latitude, longitude and altitude are present, the photo reveals exactly where it was taken.
What resolution do I need for printing?
Divide the pixel dimensions by 300 for a high-quality print, or by 150 for an acceptable one. A 3000 x 2000 photo prints 10 x 6.7 inches at 300 DPI.
Why is my image showing the wrong dimensions?
The reported dimensions are the stored pixel dimensions, which is what you control. The display size on screen depends on CSS, so a 4000px image can display at 400 CSS pixels or any other size.