1Upload the videos you want resized — work from the largest original you have rather than from a copy you already shrank once.
2Type a target width, a target height or a percentage, and leave the aspect-ratio lock on unless you deliberately want stretching.
3Run the resize; every file in the batch is taken to the same target in a single pass.
4Download the resized Video file, or the whole set together as one archive.
Resize Video 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.
How does Resize Video change the dimensions?
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Concretely, each clip is probed for its real resolution first, then scaled and re-encoded, so a batch of mixed sources lands on one target size rather than one scale factor. You give it a target width, a target height or a percentage, and it works from the original rather than from a previously resized copy.
Is there anything specific to Video I should watch for?
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Yes — the container and codec are probed before anything runs, so mixed uploads in one batch are handled per file. Worth checking before you resize a file you will not be able to regenerate.
What is the most common mistake when resizing videos?
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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.
Which video formats does Resize Video accept?
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MP4, MOV, MKV, WebM, AVI, WMV, FLV, 3GP, M4V, MPEG and MPG. Each file is probed for its real container and codec before anything runs, so a mixed batch is handled correctly file by file.
Is there a file size limit on Resize Video?
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Yes: free accounts process video up to 1 GiB per file whichever container you brought; ffmpeg with x264, x265 and libvpx does the encoding. It is high enough that upload speed is usually the binding constraint rather than the cap itself.
Will Resize Video lower the quality of my videos?
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Only if the operation requires re-drawing frames. Container-level and timeline-level work is done as a stream copy, which is bit-identical to the source and finishes in seconds. Anything that must re-encode does so at a quality level you choose.
Can I run Resize Video on several videos at once?
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Yes, and it matters here more than anywhere else — video jobs run in minutes, so queueing the batch in parallel is the difference between one wait and several.
Why does a EPUB site host Resize Video?
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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 Video 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 Video 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 Video means the conversion is made from the version you settled on, not from the one you were still fixing.
Is Resize Video 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, and nothing is kept: uploads are deleted from the workers shortly after the job finishes, nothing is read and nothing is indexed. Free accounts exist for history and batch size, not for access.