How to use it
- Drop an image into the box above.
- Type the width or height you need — the other follows if ratio is locked.
- Press Download to save at the exact new size.
~/lokafile / optimize / resize-image
Resize Image
Set an exact width and height in pixels. Lock the ratio so your image never looks stretched — all on your device.
Drop an image here, or click to choose
JPG · PNG · WebP
How to resize an image in pixels
- Add your image. Drag it onto the box above, or click to choose it. JPG, PNG and WebP all work.
- Type the target width or height. With “Lock ratio” on, the other dimension follows automatically so nothing stretches.
- Check the preview. The readout confirms the exact new dimensions against the original.
- Download. The resized image saves straight to your device.
The resizing runs in your browser, so the image never leaves your machine — no upload wait, no queue, no limit on how many images you run through it.
Common resize targets
A few sizes come up constantly: square profile photos are typically 400×400, video thumbnails 1280×720, and full-width web images around 1600px wide. Whatever the slot, type the exact dimensions it asks for — uploading at the target size is what keeps text and edges crisp, because it stops the platform from scaling the image itself. The image sizes guide has the full table of profile, banner, thumbnail and story dimensions with their aspect ratios.
Shrinking is safe; enlarging is not
These two directions are not symmetrical. Downsizing discards pixels, and the high-quality smoothing used here keeps the result sharp — a 4000-pixel photo scaled to 1600px loses nothing you can see. Enlarging invents pixels, and it shows: a small logo scaled up four times looks soft no matter which tool does it, because the detail simply is not there to recover. When something must display larger, the honest fix is a bigger original, not a bigger export.
Pixels are not kilobytes
An image has two “sizes”: the dimensions in pixels — what this page changes — and the file weight in KB or MB, which is what email limits and upload forms measure. Downsizing usually reduces both, but if the goal is a hard file-size cap, pair this tool with compression: resize down to the dimensions you actually need, then compress the result. That order produces a far smaller file than either step alone.
What comes out
A PNG comes out as a PNG, with transparency preserved exactly — useful for logos that need to sit on colored backgrounds. Everything else is saved as a high-quality JPG, where transparent areas become white. If the format itself is the thing you want to change, the PNG to JPG tool handles that with control over quality and the transparency fill color.
Resizing several images
This page handles one image at a time so the preview stays honest. For a folder of them, the Lokafile browser extension resizes in batches with the same on-device processing.
From the guides
Common Image Sizes for Web and Social Media →In your toolbar
Prefer it in your toolbar? Same tools as a free browser extension — no permissions, no uploads.
Questions people ask
Is my file uploaded to a server?
No. Every other online converter uploads your file to a server. Lokafile never uploads anything — the work happens in your browser, so your file physically never leaves your device.
Do I need to sign up or pay?
No account, no payment, no watermark, no CAPTCHA before download. Free.
Does it work offline?
Yes — once loaded, you can disconnect and it still works. You can even install Lokafile as an app.
Is there a file size limit?
No artificial cap. The only limit is your device’s memory.
How do I resize an image in pixels for free?
Drop the image into the box above, type the width or height you need — the other follows automatically while the ratio is locked — and press Download. It runs in your browser on your own device — no upload, no account, no watermark and no daily limit.
How do I avoid stretching the image?
Keep “Lock ratio” on — height follows width automatically so proportions stay intact.
Does resizing reduce quality?
Downsizing keeps images sharp. Enlarging beyond the original size can look soft, since pixels are being invented.
Does resizing make the file size smaller?
Usually, yes — fewer pixels means less data, so downsizing shrinks the file too. For the smallest possible file, resize down first and then run the result through compression.
Will a transparent PNG stay transparent?
Yes — a PNG comes out as a PNG with its transparency preserved exactly. Other formats are saved as JPG, where any transparency becomes white.