Resizing to an exact size without stretching: fill vs fit

2026-09-24

A form demands an exact size — say a square — and your photo is a rectangle. Naive resizing forces one shape into the other by stretching, and stretched faces and squashed logos are how you spot it forever afterwards. There are only two honest ways out, and every serious tool offers both.

Option one: fill (and crop the overflow)

Fill scales your image until it covers the whole target, then trims whatever hangs over the edges. The result has no borders and no distortion — the cost is that the trimmed strips are gone. Right choice when the image must look seamless: thumbnails, avatars, cards, backgrounds.

Option two: fit (and pad the gap)

Fit scales your image until the whole thing is inside the target, then fills the leftover space. Nothing is lost and nothing distorts — the cost is visible bars on two sides. Right choice when every pixel matters: product shots where the whole item must show, documents, diagrams.

In our resize tool, these two choices appear the moment you enter a width and height that don't match your image's shape — with aspect ratio kept, the question never arises, because the tool computes the other side for you. When the fit option pads, PNG output leaves the padding transparent; JPG fills it white (JPG has no transparency to offer).

The other guard: enlargement

Separate from shape is scale: a small image resized upward gains pixels but not detail — enlargement is always a blur trade. The don't enlarge switch stops a batch from quietly blowing up its smallest member; the exception is when you explicitly set both dimensions, where changing proportions is the very thing you asked for.

What we deliberately don't do

We never stretch. There is no mode in which your image's proportions are distorted to reach a target — fill crops, fit pads, and that is the entire menu. Stretching is the one option whose only output is a worse image.

The short version

• Different target shape: fill (crop, seamless) or fit (pad, complete) — never stretch.
• Fill for thumbnails and backgrounds; fit for products and documents.
• Fit-padding is transparent in PNG, white in JPG.
• Upscaling adds blur, not detail — the don't-enlarge switch guards batches.