Image Resizer
Free online image resizer. Pixels, percent, or social presets. Batch + ZIP download. Runs in your browser. No watermark, no upload, no account.
Image Resizer takes any image or batch of images, resizes them to the dimensions you pick, and hands the new files back. Pixel mode lets you set width and height directly with an aspect-ratio lock, or pick from common presets (1920w, 1280w, 800w, IG square, IG portrait, Story, X header). Percent mode scales by 5%–400%. Same settings apply to every file in the batch.
"Resize image online" results lean heavily on upload-and-wait services that cap your batch, watermark the output, or convert your PNG to a JPEG you didn't ask for. None of that is necessary. Image Resizer scales everything client-side with the browser's high-quality canvas resampler and lets you keep the format you started with.
- 01Drop one image, or a batch. PNG, JPG, WebP, GIF, BMP, and AVIF all accepted.
- 02Pick a mode: Pixels for exact dimensions, Percent for a scale factor that applies per file.
- 03In Pixels mode, click a preset or type into W / H. The 🔒 lock keeps the aspect ratio of the source so you only enter one dimension.
- 04Pick a format: Auto keeps PNG/JPG/WebP inputs as-is, or force JPEG / PNG / WebP. Quality slider applies to JPEG and WebP.
- 05Click Save on any row to download just that file, or Download ZIP for the whole batch.
- Aspect lock is on by default in Pixels mode. With it on, the H input is computed from W using the source ratio. Turn it off to stretch.
- Percent mode applies per file: 50% on a 4000×3000 photo gives 2000×1500; 50% on a 800×600 logo gives 400×300. Useful for cutting a whole folder in half.
- Auto format means JPG stays JPG, PNG stays PNG, WebP stays WebP. Everything else outputs as PNG (lossless safety net).
- Quality slider only fires on JPEG and WebP. PNG is lossless and ignores quality.
- Resizing larger than the source upscales with bilinear smoothing. You won't gain real detail.
- Nothing leaves your machine. No upload, no server, no account.
Is Image Resizer really free, and does it add a watermark?
Yes, it’s free. No account, no upload, no watermark on the output, ever.
What input and output formats does it support?
Input: PNG, JPG, WebP, GIF, BMP, AVIF. Output: Auto (preserve PNG/JPG/WebP, fall back to PNG for others), JPEG, PNG, or WebP, your pick.
How do I resize without distorting the image?
Leave the 🔒 aspect lock on (default in Pixels mode), then type just one dimension. The other follows the source ratio. Percent mode also preserves the aspect ratio by definition.
Can I batch-resize a folder of photos to the same size?
Yes. Drop them all at once (or use the + Add more zone to keep stacking), pick your dimensions, and Download ZIP gives you a single archive with every file resized identically.
Will it preserve transparency?
If you pick PNG or WebP output, yes. JPEG can't store transparency — pixels behind transparent areas become white in JPEG.
Can I resize images larger than the source?
Yes, up to 16000 pixels per side. The browser upscales with bilinear smoothing. You won't gain real detail, just bigger pixels.
Does it support the Instagram / TikTok / X size presets?
Yes. IG square (1080²), IG portrait (1080×1350), Story / TikTok (1080×1920), and X header (1500×500) are one-click presets in Pixels mode.
Where does my image go?
Nowhere. The file stays in your browser tab. There is no upload and no server processing.
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