RECOMMENDATIONS

Choosing a video format for YouTube Shorts

MP4 with H.264 and AAC is a practical export choice consistent with YouTube’s encoding guidance. It is not the only supported combination. Shorts eligibility also depends on shape and duration, not the container alone.

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Platform reference and evidence

These reference values have partial source coverage. Ratios and dimensions are editing guidance; account and upload-surface limits can differ. Approximate or unknown values do not certify eligibility.

Platform
YouTube Shorts
Editing ratio
9:16 or 1:1
Max length
up to 3 minutes
Max file size
256 GB overall upload cap; Shorts duration rules still apply

Duration and size: reference and limitations. Approximate values still need confirmation in your composer.

Format reference scope: YouTube video uploads; Shorts also requires an eligible shape and duration. Source checked 2026-09-12; this does not verify every reference field. YouTube supported file formats

Full YouTube Shorts spec cheat sheet

Why this choice

A documented encoding option; other containers and codecs can be accepted.

Encoding guidance; Shorts shape and duration are separate eligibility rules. Official reference

Prepare a copy in Koldflux, review its output and check the current destination requirements before publishing.

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