What Image Resizer helps you do

Change an image to exact pixel dimensions without uploading it to Haivix. The tool reads the original width and height, keeps the aspect ratio locked by default, previews the resized result, and produces a downloadable copy. It works on a single file or a batch: set percentage or pixel mode once, add several images, and receive a ZIP with the new size in every filename.

Images are decoded and redrawn on a canvas in your browser. No file is uploaded, and no resized copy is stored on a server.

How it works

Each file is decoded by the browser, drawn onto a canvas at the target size with high-quality smoothing, and exported in the source format. Percentage mode multiplies the natural dimensions; pixel mode uses the width you enter and derives the height from the aspect ratio unless you unlock it. The canvas has a pixel-count guard, so an extreme upscale is rejected instead of freezing the tab. Batch results are packaged with the final dimensions in each filename. Because the work happens per file in the page, a slow phone takes longer on a large batch but never uploads anything.

How to use Image Resizer

Add the source image and leave aspect ratio locked unless you intentionally need a different shape.
Choose percentage or pixel mode, then enter the required width, height or scale.
Preview the resized result, then download the image or the batch ZIP.
Crop first if you need exact width and height with a different aspect ratio.

When to use it

Shrink phone photos before attaching them to an email or a support ticket.
Create thumbnails at a fixed width for a blog, shop or dashboard.
Meet an API or marketplace limit that specifies exact pixel dimensions.
Scale a screenshot to fit a slide or a documentation column.
Produce a batch of images at the same size without opening a desktop editor.
Prepare images for a retina layout where the file must be twice the display size.
Normalize a set of mixed phone photos before uploading them to a CMS.

When not to use it

Do not upscale a small image and expect new detail; the extra pixels are interpolated.
Do not use it to crop or change the aspect ratio; crop first, then resize.
Do not treat resizing as compression; run the result through the Image Compressor when weight still matters.

Example

A folder of 40 product photos at 4032×3024 needs 1200×900 thumbnails. Pixel mode with the aspect lock at 1200 produces 1200×900, and the batch export returns a ZIP whose filenames include the final dimensions. The originals stay untouched on disk. A second pass at 400 px wide creates the mobile card variants from the same source set, so both sizes match the grid.

What you can do with Image Resizer

Read and display the source image dimensions.
Resize by percentage from 1% to 500%.
Set an exact width and height in pixels.
Keep proportions synchronized with aspect-ratio lock.
Process a batch of images with one settings pass.
Download a single image or a ZIP of the resized set.
Review the result before committing the download.

Example: prepare a consistent article thumbnail

Add the source image, leave aspect ratio locked, and enter the required width. Review the calculated height and preview the resized result before downloading.

If the publishing system needs an exact width and height with a different shape, crop the source to that aspect ratio first. Turning off the lock and forcing both dimensions can stretch faces, logos, and circles.

For a product grid, decide the target box once and reuse the same settings for the whole batch. Consistent dimensions are easier to scan than images that were each resized to a different height.

When the set mixes orientations, resize to the longest edge rather than the width. A portrait and a landscape image then share a visual scale, and the layout can handle the different shapes without one image looking tiny.

What to know before you start

Upscaling creates more pixels but cannot restore detail missing from a small source.
The output keeps the source format when the browser supports it, while the download filename is standardized.
Resizing changes dimensions; use Image Compressor when file weight remains too high after resizing.
Very large pixel counts are rejected to keep the tab responsive.

Common mistakes

Unlocking the ratio and forcing square dimensions on a portrait photo, which stretches the subject.
Resizing to a width smaller than the container and then letting the browser upscale it again.
Using percentage mode when the destination specifies exact pixels.
Resizing an already-compressed JPEG several times instead of starting from the original.
Forgetting that a batch applies the same settings to every file in the list.
Choosing a target width below the CSS display size and wondering why the page looks soft.
Letting a batch include a screenshot with a different aspect ratio and expecting a uniform grid.

Troubleshooting

If the height field is ignored, the aspect-ratio lock is still enabled. Unlock it only when a non-proportional result is intentional.

If the tool refuses an output size, the pixel count exceeds the browser guard. Choose smaller dimensions or split the batch.

If the result looks soft, the source was smaller than the target. Resize down from a larger original, or accept that upscaling cannot add detail.

If one file in a batch fails, its format may not be decodable by the browser. Convert it first, then add it to the resized set.

If the downloaded ZIP is missing a file, check the batch list before exporting; a file rejected at load time never enters the queue.

If the exported image is much heavier than expected, resize before compressing rather than the other way around. A large canvas saved at high quality produces a large file even when the dimensions look modest.

Image Resizer