Question 1

Is resizing images free?

Accepted Answer

Yes. Resizing JPG, PNG, and WebP images is completely free with no sign-up, no watermark, and no file limit. Resizing runs entirely in your browser, so there is nothing for us to charge for. Pro plans add the AI tools, but everyday resizing stays free forever.

Question 2

Are my images uploaded to a server?

Accepted Answer

No. OpusImg resizes images on your own device using WebAssembly and your browser's own canvas. Your files never leave your computer or phone — there is no upload, no cloud processing, and nothing stored on our side. That makes it safe for confidential documents, client work, and personal photos.

Question 3

How do I resize an image to exact pixel dimensions?

Accepted Answer

Choose the "By dimensions" mode and type the width and height you need in pixels. Leave the aspect-ratio lock on to keep the image's proportions — change one field and the other follows automatically. Turn the lock off when you need an exact, possibly non-proportional canvas, such as a specific banner size.

Question 4

What is the lock aspect ratio toggle for?

Accepted Answer

When the lock is on, the width and height stay proportional: setting the width to 1000px updates the height to match the original shape, so the picture is never squashed or stretched. When the lock is off, you can set width and height independently, which is useful for fitting an exact canvas even if it distorts the image slightly.

Question 5

Which resampling algorithm should I pick?

Accepted Answer

Use Lanczos for photographs — it produces the sharpest, most natural result and is the default. Bicubic is a fast, smooth alternative handled by your browser. Choose Nearest neighbour only for pixel art, sprites, or icons where you want hard edges and no blending between pixels when scaling up.

Question 6

What does the DPI setting do?

Accepted Answer

DPI (dots per inch) is metadata that tells print software how large to print the image. It does not change the pixel dimensions or how the image looks on screen — 72 DPI is standard for the web, while print shops usually want 150 or 300 DPI. We embed the value you choose into the file (PNG and JPG) so a print workflow reads the right density.

Question 7

Can I resize for Instagram, YouTube, or other platforms?

Accepted Answer

Yes. The "By preset" mode includes 18 ready-made sizes — Instagram square, portrait, and story; Facebook and LinkedIn covers; X/Twitter headers; YouTube thumbnails and channel art; Pinterest pins; plus HD, QHD, and 4K. Pick a preset and your image is resized to the exact canvas that platform expects.

Question 8

Will resizing reduce image quality?

Accepted Answer

Making an image smaller (downscaling) keeps it looking crisp — Lanczos and bicubic both average pixels cleanly. Making it larger (upscaling) can only invent so much detail, so very large enlargements look soft; for big upscales the AI upscaler in Pro reconstructs detail far better. We encode the result at high quality so the resize itself adds no visible compression artifacts.

Question 9

Can I resize many images at once?

Accepted Answer

Yes. Drop a whole folder and apply one target to the batch. In percentage mode every image is scaled by the same percentage, so each keeps its own aspect ratio; in dimensions or preset mode every image is fitted to the same canvas. Results are bundled into a single ZIP for download, all processed on-device.

Question 10

What formats can I resize?

Accepted Answer

You can drop in JPG, PNG, WebP, AVIF, GIF, BMP, TIFF, and HEIC. Each file is decoded in your browser, resized, and re-saved — JPG and HEIC come out as JPG, PNG/BMP/TIFF as PNG, and WebP/AVIF/GIF as WebP, so the result always opens everywhere. To change format deliberately, use the converter tool linked below.

One photo, every social size