What does a video resolution converter do?
Video resolution is the frame width and height in pixels. Converting resolution usually means changing these dimensions while keeping the same aspect ratio. This calculator scales the other dimension proportionally, so a 1920 × 1080 frame resized to 1280 pixels wide becomes 1280 × 720.
How proportional scaling works
If you choose a target height instead, the width is calculated as target height × source width ÷ source height. The displayed result is rounded to the nearest whole pixel. Some codecs and editing workflows prefer even dimensions, so check your export requirements before rendering.
Resize, crop, or stretch?
- Resize proportionally: changes the pixel dimensions while keeping the same shape.
- Crop or reframe: changes which parts of the frame are visible to fit a different shape.
- Stretch: changes the shape of objects and is usually undesirable for normal footage.
For example, converting widescreen 16:9 footage to vertical 9:16 is not a simple proportional resize: it requires reframing or cropping because the aspect ratio changes. Use the aspect ratio calculator to compare formats, or the image aspect ratio checker for image crops.
Frequently asked questions
Will this converter resize my video file?
No. It calculates the correct dimensions only. Use your video editor or encoder to apply the new resolution to the actual file.
Why are dimensions rounded?
Pixels must be whole numbers. The closest integer dimensions preserve the ratio as closely as possible; some encoding formats may also require even dimensions.
Can I convert 16:9 to 9:16 without cropping?
Not while filling the whole frame and preserving the original image shape. You can place the landscape video inside a vertical canvas with empty space, or crop/reframe it to fill the canvas.
Check the ratio before you resize.
Open aspect ratio calculator