Free Online Image OptimizerCropping to the part that matters
Cropping is the one edit on this site that is free in every sense. It removes pixels rather than altering them, so what remains is bit-for-bit what the camera recorded, and the file gets smaller because there is less of it. No other change here can claim both.
Removing pixels costs nothing in quality
This is worth stating plainly because it is not true of the neighbouring controls. Resizing recalculates every pixel from its neighbours. Changing quality discards information deliberately. Cropping does neither: the pixels you keep are untouched, and the ones outside the rectangle simply stop being in the file.
So crop as hard as the composition allows before reaching for anything else. A photograph reduced to the half that has the subject in it is already half the size, with nothing given up.
Press the crop tool, then drag the region
Stage the picture and look at the row of three small tools underneath it. The first is the crop tool; the other two flip the picture. Nothing is cropped until you press it, which is deliberate — a rectangle sitting on every photograph the moment it arrives reads as a demand rather than an offer.
Press it and a rectangle appears with a handle at each corner. Drag inside to move the whole thing, pull a corner to resize, and the area outside dims so the framing is easy to judge. Use this region applies it and Whole image puts it back, so nothing is committed by experimenting.
The region is stored as proportions of the picture rather than pixel coordinates, which is why it survives whatever you do next. Change the output width afterwards and the same part of the photograph is still the part you kept.
Checking the cut before you commit to it
Two controls beside the region are worth knowing. Before / after swaps between the cropped version and the original, which is the quickest way to see whether you have taken too much — a crop that looked bold while you were dragging often looks tight the moment you can compare it.
Reset abandons every edit on the picture and returns to the file you brought. It covers the flips as well as the crop, so it is the way back from any amount of experimenting rather than an undo of the last thing.
When the framing is right, save. The cropped picture is compressed on the way back like anything else here, so the saving you see combines the pixels you removed with the compression applied to the ones you kept.
Worth knowing
One picture at a time, deliberately
This page takes a single image where most others take twenty, and the limit is real rather than unfinished work. A crop region is chosen against a particular composition. Applied unchanged across a set, the same rectangle takes the subject out of most of them, and a tool that quietly ruined nineteen photographs to save time on one would not be worth having.
Cropping an animation
An animated GIF is cropped without being flattened, and without being re-encoded frame by frame — the request is passed to our image service as an instruction and every frame survives it. The animation page is where that belongs.