Video Resolution vs File Size: Compare What Changed

Calculate the pixel-count change

Multiply width by height to compare the number of pixels in one frame. For 360 × 640, the result is 230,400. For 180 × 320, it is 57,600. The smaller frame contains one quarter as many pixels, a 75% decrease.

Halving both width and height does not halve pixel count. This is a useful check when a preset changes two dimensions at once. It still says nothing by itself about detail retained by a codec.

Original pixels = 360 × 640 = 230,400
Export pixels = 180 × 320 = 57,600
Change = (57,600 / 230,400 - 1) × 100 = -75%

Check whether the clips are comparable

A portrait crop and a landscape source can have different framing even when both look acceptable. A shorter export can be smaller because it contains less time. A comparison that ignores those changes can point you toward the wrong setting.

Run a controlled comparison

1. Choose source and export copies in Export Check and note the measured dimensions.
2. Check duration and file size before drawing a conclusion from the pixel-change metric.
3. Use a matching timestamp, then inspect the same visible detail in both previews.
4. Download the comparison report so you can compare another export under the same conditions.

Decide what the number can justify

A measured resolution drop justifies checking a resolution or crop choice in your editor. It does not prove that every visible difference was caused by that drop. Different motion, encoding and playback conditions can change the result too.

Export Check does not resize, upscale or transcode files. Its report is useful for documenting an observed change and planning the next test. Keep the original footage and use a dedicated editor for an intentional output adjustment.