Resize without stretching. Keep the shape, change the size.
Enter the original width and height to find the ratio, then type one new side and get the other. The frame on the right draws the result to scale, and flags sizes that would give fractional pixels.
When the ratio changes, you can't keep the whole picture and fill the frame. Pick a source and a destination to see the three options and exactly how much each one costs.
Each shape is drawn to scale at the same height, so you can compare them directly. Click one to load it into the calculator.
DV, HDV, broadcast SD and anamorphic lenses store frames with pixels that are wider or narrower than they are tall. The player stretches them on playback, using a pixel aspect ratio (PAR) written into the file. Ignore it and circles turn into ovals. Pick a format or enter your own; every value below is computed from your inputs.
-vf "setsar=10/11" (or setdar=15/11)-vf "scale=654:480,setsar=1"aspect_ratio_idc = 3 (Table E-1: 10:11)00 00 00 10 70 61 73 70 00 00 00 0a 00 00 00 0b (hSpacing 10, vSpacing 11)PixelWidth 720, PixelHeight 480, DisplayWidth 654, DisplayHeight 4802560 × 1080 reduces to 64:27, which is 2.370. Real sizes rarely reduce to small numbers, so they get named after the nearest simple fraction. Continued fractions find those best approximations step by step: each convergent is the closest fraction possible for its denominator size. Enter a size like 3440×1440 or a decimal like 2.39.
[2; 2, 1, 2, 3]H.264 splits every frame into 16 × 16 macroblocks. 1080 isn’t a multiple of 16, so a 1080p stream is coded as 1088 rows and the extra 8 are cropped on playback. With 4:2:0 colour, the crop works in 2-pixel steps, which is why odd widths fail. The table computes this for any size, and the button asks your browser’s own encoders whether they accept it.
avc1.640033check_circlesupportedhvc1.1.6.L153.B0cancelrejectedvp09.00.51.08check_circlesupportedav01.0.13M.08check_circlesupportedThe first table uses your calculator’s original size (1920×1080); the last column is tested in this browser.
aspect-ratio: 16 / 9;Box Sizing Level 4. Sets the preferred ratio; an explicit height or min-height on the box still wins.supported<img width="1920" height="1080">Browsers map the attributes to aspect-ratio: auto w / h, so space is reserved before the image loads.auto 1920 / 1080padding-top: 56.25%;Percentage padding resolves against the width, so height = width × h/w. Needed before 2021.still works@media (min-aspect-ratio: 16/9)Compares the viewport’s width/height. device-aspect-ratio is deprecated.viewport does not matchcontain · cover · fillThe fit, fill and stretch options shown above, for img and video.supported-vf "scale=-2:1080,setsar=1"-2 keeps the ratio and rounds to an even number for 4:2:0 video.command linewidth 1920.0, height 1080.0 (16.16 fixed point)Track display size; players combine it with pasp and the codec’s VUI.file metadataaspect_ratio_idc 1 = squareTable E-1 lists 16 preset pixel shapes; 255 means explicit sar_width and sar_height.bitstreamOrientation (tag 0x0112) = 6No ratio field. Orientation values 5-8 rotate by 90°, swapping width and height on display.file metadataDisplayWidth 1920, DisplayHeight 1080DisplayUnit 3 means the values are a ratio rather than pixels.file metadataTools that resize or crop a real file to the size you just worked out.