Free conversions have a size limit per file, set by the type of file, and the page tells you when a file is over it. A paid plan removes that limit, so much larger files can be converted.
ئایا پێویستم بە حسابێک هەیە، ئایا هیچ شتێکی تێدایە؟
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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.
