Free Image Resize Online — Resize JPG & PNG Without Losing Quality

Free Image Resizer Online

FJ Techtools provides a free image resize online tool that lets you change the dimensions of any JPG, PNG or GIF image up to 5MB — no software installation and no signup required. Whether you need to resize a photo for a website, shrink an image for an email attachment, or scale down a screenshot for a blog post, this tool handles it in seconds.

You can resize by percentage (e.g. scale to 50% of the original size) or by entering exact pixel dimensions for width and height. The aspect ratio lock is on by default, so your image never gets stretched or distorted — unlock it only when you need non-proportional resizing.

How to resize an image online in 3 steps

Upload

Click "Select Image" or drag and drop your JPG, PNG or GIF (up to 5MB) into the upload area.

Resize

Choose to resize by percentage or by exact pixel dimensions. Toggle the lock icon to maintain or break the aspect ratio, then click "Resize Image".

Download

Click "Download Image" to save your resized image. The file downloads directly to your device — ready to use immediately.

When do you need to resize an image?

Image resizing is one of the most common tasks in everyday digital work. Here are the most frequent use cases:

Websites and blogs — oversized images slow down page load times. Resizing to the exact display dimensions improves performance and Core Web Vitals scores.
Social media — every platform has recommended image dimensions. Facebook covers, Instagram posts, Twitter headers, and LinkedIn banners all have different optimal sizes.
Email attachments — most email clients have attachment size limits. Resizing a photo before attaching it avoids bounce-backs and speeds up delivery.
E-commerce product images — consistent image dimensions make product listings look professional and load predictably on all devices.
Presentations and documents — embedding a 4000×3000px photo into a Word document or slide deck creates unnecessarily large files. Resizing first keeps file sizes manageable.

Resize by percentage vs. by dimensions — which should I use?

Resize by percentage is the easiest option when you want to make an image generally smaller without worrying about exact pixel values. Entering 50% halves both the width and height. This is ideal for quick size reductions.

Resize by dimensions gives you precise control. Enter the exact width or height in pixels and the tool calculates the other dimension automatically (when aspect ratio lock is on). Use this when a platform specifies exact pixel requirements — for example, a 1200×630px Open Graph image or a 800×800px product thumbnail.

Frequently Asked Questions About Image Resizer

Can I resize an image without losing quality?

Reducing an image's dimensions generally preserves quality well, since fewer pixels need to be displayed. Enlarging an image beyond its original size will reduce quality as pixels are interpolated. For best results, always resize down rather than up.

What image formats does this tool support?

This tool supports JPG/JPEG, PNG and GIF images. The resized image downloads in the same format as the original.

Does this tool upload my image to a server?

Yes. Your image is uploaded to our server so it can be resized, and the resized file is then sent back for you to download. No account is needed and we do not share your images.

What is the difference between resizing by percentage and by dimensions?

Resizing by percentage scales the image proportionally — entering 50% halves both the width and height. Resizing by dimensions lets you set exact pixel values for width and height, with an optional aspect ratio lock to prevent distortion.

How do I resize an image to a specific size in KB?

Resizing by dimensions reduces file size indirectly — smaller pixel dimensions produce smaller files. For direct file size control, use the image compressor after resizing.

Is there a file size limit for uploads?

The tool accepts image files up to 5MB. For larger files, use the Compress Image tool first to reduce the file size before resizing.

Supported image formats

This tool supports the most widely used raster image formats: JPG/JPEG, PNG and GIF. The resized image downloads in the same format as the original.

Free image resize online tool — resize JPG and PNG by dimensions or percentage

Resize Image Online