Distinguish between extension and actual image format
The name photo.jpg is not evidence that the file is a JPEG. Even if you change the name, the internal PNG data remains the same. File diagnosis distinguishes PNG, JPEG, WebP, and GIF headers, and opens PNG, JPEG, and WebP still images in the browser to check pixel size and transparent areas. If the file name and actual format are different, separate instructions will be provided.
GIFs and animations only display header information. It is not the result of inspecting every decoded pixel or every frame. HEIC, AVIF, and SVG are not supported. The malware scan does not end just because the file is opened.
Independently check 100KB·width·height conditions
- Select file for image file diagnosis.
- Enter the maximum capacity of the submission destination in KB. 100KB is 100,000 bytes in this tool, and 100KiB is 102,400 bytes.
- Enter the exact width and height required. Empty items are not checked.
- Select the required format and check whether each item passes or not.
For example, a 1199×900 PNG of 99,000 bytes is less than 100KB, but the width and format do not match the 1200×900 JPEG conditions. “Conditions passed” only refers to the items entered. It does not check DPI, color profile, or policies of the submission site.
Moving from inspection results to necessary actions
If the pixel sizes are different, compare Crop and Add Margin in the Scale Tool. You can choose actual format conversion if the format is different, or target size compression if the size is large. Clicking Move Between Tools temporarily stores the selected files in browser storage and deletes them after loading them in the next tool. No files are uploaded to the server.
The entered maximum capacity, exact width, height, and format conditions are also transmitted within the browser along with the file. Rate changes and format conversions re-check this condition in the save results. If there is an exact pixel condition, compression will check if the original size is the same as the condition and will not do any pixel reduction. Files that do not meet the capacity are marked as not meeting the requirements and excluded from the ZIP.
Compression target is 10~10000KB and supports JPEG or WebP. Capacities or PNG submission conditions that are out of range will not be processed and will be informed. To save as PNG, please change the proportions or convert format and check the final size. You can remove inherited conditions by clicking Release Submission Conditions.
Frequently Asked Questions
How do I check if the background is transparent?
Decode the supported still images and check if any pixels have an alpha value less than 255. Even if the format can accommodate transparency, all pixels may be opaque. Transparent areas in GIFs and animations are not confirmed.
Is upload guaranteed if the file diagnosis passes?
No. This function compares with directly entered conditions. File inspection, DPI/profile conditions and other policies of the submission destination must be checked separately.