How to resize an image
- Add your images. Drag and drop your photos onto the dropzone, click to browse, or paste from the clipboard. JPEG, PNG, WebP, AVIF and GIF are all supported, and you can add several at once.
- Choose pixels or percentage. Pick “Percent” to scale by a ratio (great for whole batches), or “Pixels” to type an exact width or height. Keep aspect ratio on to avoid stretching.
- Set format and quality (optional). Leave the format as “Same format” to keep the original type, or convert to WebP or AVIF for a smaller file. Adjust the quality slider to compress at the same time.
- Download your resized images. Each image is resized on your device with Lanczos resampling. Download them individually or grab everything at once as a ZIP.
Why resize your images?
Modern phones and cameras capture enormous images — a single photo can be 6000 pixels wide and weigh ten megabytes or more. That is far more detail than almost any screen, email, or web page will ever show. A blog header might display at 1200 pixels wide; a profile picture at 400; an email signature at 150. Shipping a 6000-pixel file into a 1200-pixel slot wastes bandwidth, slows page loads, and bloats attachments for no visible benefit.
Resizing is also the most powerful lever you have on file size. Because an image’s data scales with its total pixel count, halving both the width and height removes roughly three-quarters of the pixels — and therefore most of the file size — before any compression even happens. Lowering JPEG quality might trim 30–50%; resizing a too-large photo to its real display size routinely cuts 80–95%. If a file feels too big, resize first and compress second.
And because this tool runs entirely on your device, it is the private way to do it. Other online resizers upload your photos to a remote server, process them there, and send them back. Here your images are read into memory, resized locally, and handed straight back — they never touch a network.
How resizing affects quality
Downscaling — making an image smaller — is inherently gentle on quality, but how the pixels are combined matters a lot. Naive scaling simply throws away pixels, producing jagged edges and shimmer on fine detail. This tool instead uses high-quality Lanczos resampling, which weighs a neighborhood of surrounding pixels for each output pixel. The result keeps edges crisp and text legible, so a downscaled image looks clean rather than blurry or aliased.
The one operation that genuinely hurts is upscaling — enlarging an image beyond its original dimensions. No resampler can invent detail that was never captured, so an upscaled photo looks soft and mushy. As a rule, only ever resize down: choose the largest size you actually need and resize to that, never above the source dimensions. When you also convert to a lossy format, remember that compression and resizing stack — a resized image has fewer pixels to compress, which is exactly why the two together produce such small files.
Pixels, percentage, and common target sizes
Percentage mode is ideal for batches: set 50% and every image shrinks proportionally regardless of its starting size. Pixel mode is for precise targets — type a width (or a height) and, with aspect ratio locked, the other dimension is calculated for you so nothing is stretched. The aspect ratio is just the relationship between width and height (16:9, 4:3, 1:1); keeping it intact is what stops faces and logos from looking squashed. You can read more about how images and their dimensions work on MDN’s guide to images on the web.
Useful targets to keep in mind: most web content looks great between 1200 and 2000 pixels on the long edge (use the larger end for full-width hero images on high-density displays). Email attachments and signatures should usually stay at or below 800 pixels to keep inboxes happy. For social media, common dimensions are roughly 1080×1080 for a square Instagram post, 1080×1920 for vertical stories and reels, 1200×630 for a Facebook or Open Graph link preview, and 1500×500 for an X/Twitter header. When in doubt, resize to the largest place the image will appear and let the platform scale down from there.
Tips for the best results
- Never upscale. Enlarging past the original size only adds blur. Pick the biggest dimension you truly need and stop there.
- Resize before you compress. Fewer pixels means a smaller file and less work for the encoder. For the smallest photos, resize here and then run them through JPEG compression.
- Lock the aspect ratio. Enter only width or only height and let the other auto-fill — it is the easiest way to avoid stretched, distorted images.
- Convert while you resize. Switching to WebP or AVIF with the image converter can shrink a resized photo another 25–50% with no visible quality loss.
- Keep your originals. Resize from a full-resolution master each time rather than re-resizing an already-shrunken copy, which compounds quality loss.