Threads video aspect ratio runs 0.01:1 to 10:1: Sume Timeline sizes

Almost any shape works for Threads, and 1080x1920 is the safe pick. Meta's Threads API page lists aspect ratio "0.01:1 to 10:1" with 9:16 recommended, a maximum horizontal resolution of 1920 pixels, and 23 to 60 frames per second. Sume's Timeline renders 1080x1920 by default, which is 9:16 and under 1920 on its width. Choose other sizes only if the creative needs them.

Sizes that satisfy both sides

Each Sume size uses even integers inside Timeline's 256 to 2160 range.

Steps

• Leave output unset for 1080x1920, or set width and height explicitly.
• Set output.fps to 24, 25, 30 or 60. All four are inside the 23 to 60 range.
• Use fit: "cover" when the source already has the right shape, contain when you must keep the whole frame, and blur when you want the leftover space filled.
• Run the unbilled POST /v1/timeline-1.0/plan first.
• Keep duration at 300 seconds or less.

Wide Timeline outputs above 1920 pixels are legal in Sume and not on Threads, so the Sume range is not the Threads range.

Picking a size for a feed post

Because Threads accepts such a wide range of ratios, the choice is a creative one. A 1080x1920 vertical gives the most screen height on a phone and matches Meta's stated recommendation of 9:16. A 1080x1080 square suits a product shot that must also work in a grid. A 1080x1350 4:5 sits between them.

Whichever you pick, keep the width at 1920 or less. Sume allows up to 2160 on either side, so it will happily render a wider file than Threads accepts. The unbilled plan call does not check against Threads, so the limit is yours to hold.

If the same video will go to other places, render the vertical first, then use the crop filter for the square and 4:5 versions, at $0.02 each.

Budget and detail

The 0.01:1 to 10:1 range on Meta's page is very wide, and it is a rule about what the API accepts, not advice about what looks good. A 10:1 strip would be 1920 by 192 pixels, which is legal on the Threads page but tiny on a phone. Pair the rule with a look at the result on a real device, and stay with the shapes people expect unless the creative needs something else. Sume's own limits sit inside the range: the smallest output side is 256, and the biggest is 2160.

What Sume does not do

Sume does not check the output against Threads' ratio rule. It also does not offer a letterbox-with-your-color mode; the four fit modes are cover, contain, stretch and blur.