1Upload the BMP images you want resized — work from the largest original you have rather than from a copy you already shrank once.
2Set the new size: for an image, a width and height in pixels with an optional aspect-ratio lock; for a video, one of the preset sizes from 1920x1080 down to 640x360.
3Start the resize; the picture is scaled to the size you chose.
4Download the resized BMP file.
Resize BMP FAQ
What dimensions should I actually target?
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Match the slot it will live in. A full-width web hero rarely needs more than 1920 pixels wide, a content image 1200, a thumbnail 400, and doubling those numbers covers high-DPI screens. Anything beyond that is bytes nobody sees.
Is there anything specific to BMP I should watch for?
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Yes — because nothing is compressed, a BMP is fast to read and edit but punishing to upload, and it carries no metadata to preserve. Worth checking before you resize a file you will not be able to regenerate.
What is the most common mistake when resizing BMP images?
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Upscaling. Enlarging cannot invent detail that was never captured, so the result is a soft version of the original at a bigger size. Always resize down from the largest source you have, and resize once rather than in stages.
Is there a file size limit on Resize BMP?
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Yes: free accounts process images up to 5 MB each; lossless sources hit that ceiling sooner than photographs do, because nothing has been thrown away yet. If you are over it, converting to PNG first is often enough on its own — a BMP is routinely ten to twenty times the size of the identical image as PNG.
Can I run Resize BMP on several BMP images at once?
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Yes — upload the set and they process in parallel under one set of settings. Lossless files are larger, so a big batch is bound by your upload speed rather than by the processing itself.
Why does a EPUB site host Resize BMP?
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EPUB.to is built around the open eBook format — XHTML in a zip, reflowable by design, and readable on hardware nobody has thought about the layout for. A book is a zip full of markup, images and fonts, so almost every job people bring to an eBook site is really a job on one of those things. Resize BMP runs on the same upload and the same account as the conversions because that is where it is needed.
What should I do with the result once Resize BMP is finished?
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The converter on this site moves books between EPUB, MOBI, AZW3, PDF and DOCX, so a title ends up on whatever hardware is actually going to read it. Doing that after Resize BMP means the conversion is made from the version you settled on, not from the one you were still fixing.
Is Resize BMP here the same tool the sibling sites run?
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The engines are shared — the same toolchain, the same workers, the same limits. What a EPUB site adds is a view on reflow: which of these operations a reflowable book genuinely supports, and which ones only make sense on the fixed-layout media inside it. It also starts from one fact about the format this site is named after: the book is a zip of XHTML with a manifest, so the text costs almost nothing and every decision that matters is about the embedded images and font subsets.
Do I need an account, and does anything get kept?
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No account is needed. Uploads and results are kept for about 24 hours, which leaves time to download the result, and are then deleted automatically; nobody reads, lists or indexes them. Several files in one job need a paid plan.
