Read the file, not the filename
The inspector checks the GIF signature and walks the image and extension blocks. It counts image descriptors, reads hundredths-of-a-second delays and reports a recognized looping extension. It does not trust the filename or infer animation length from the file size. If the structure is incomplete, it shows an error rather than a guessed answer.
Understand the numbers
Canvas dimensions describe the whole image area; individual frames may update smaller rectangles. Exact bytes count the complete selected file, including metadata. KiB divides that number by 1,024. The cycle duration adds stored image-frame delays once, even when the file requests infinite looping. A missing loop extension is reported as unspecified, not treated as proof of infinite playback.
A practical check before sharing
Export a greeting from the maker, save it, then select that download here. Compare its measured dimensions and size with the maker result. A compact 240-pixel GIF has fewer pixels than a 480-pixel version, but the actual byte reduction depends on the artwork. Check the text visually in the receiving app as well: these metadata do not measure readability.
What stays on your device
File contents are read into this tab to inspect the metadata. There is no upload request, remote conversion, account or saved file history. Clear selected file removes the result and local report link; reloading also clears them. A report you explicitly download remains on your device. The report excludes the selected filename. Normal website hosting requests still occur.
Limits of this inspection
The inspector does not decompress image pixels, preview an arbitrary GIF, repair corrupt image data or certify file safety. A readable block structure can still contain invalid compressed pixels. Files are limited to 20 MiB and 10,000 image frames to bound local work. For frame-by-frame inspection of a greeting you are creating here, use the maker timeline.
Change the frame delay · Make a GIF · File-size guide · Local-file privacy