A file-size tool built for upload limits
Many application portals ask for a photo or signature within a precise file-size range. This tool focuses on the number the portal checks: the final byte size.
When an image only needs to become larger, its original pixels and metadata can remain untouched. When it needs to become smaller, the browser searches for a suitable quality and resolution.
Nothing to queue and nothing to upload
Processing happens locally with browser image APIs and a background worker. Your source image is not sent to this website, an image API, or cloud storage.
JPG, PNG, and WebP are supported in the first release. Animated GIF, SVG, and HEIC are rejected clearly instead of being silently converted.
Choose the target from the receiving form
Start with the upload rule rather than an arbitrary file size. Record whether the form publishes a minimum, a maximum, or an exact target; then check its accepted format, pixel dimensions, aspect ratio, and filename rules. A file can have the correct number of bytes and still be rejected for a different requirement.
This site measures decimal units, so 50 KB means 50,000 bytes. Some operating systems display binary units while labeling them KB, which can make an exact result look slightly different in a file manager. The byte count shown by the tool is the value used for processing and verification.
Use the right strategy for increasing or reducing
If the source is smaller than the target, the safest approach is to keep its image data and add valid trailing bytes. The downloaded file remains the same format and retains the same visible pixels. This satisfies a minimum file-size rule, but it does not create new photographic detail or improve a blurry source.
If the source is larger than the target, the browser must encode it again. JPEG and WebP support adjustable quality, so the tool searches for the strongest result that fits. It tries the original dimensions first and only considers fewer pixels when quality changes alone cannot reach the requested size.
Check the downloaded image before submitting it
Open the result once on your device and inspect the areas that matter: a face, signature strokes, printed text, transparent edges, or small product details. Then confirm the file extension and exact byte count against the destination instructions. Keep the original source until the receiving portal accepts the result.
For a maximum-size rule, a target slightly below the published limit can be safer when the portal does not explain whether it uses decimal KB or binary KiB. For a minimum-size rule, an exact byte-checked result avoids unnecessary re-encoding and repeated upload attempts.