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Image Resizer

Media

Drag images onto this panel or paste them from the clipboard. JPEG, PNG, WebP, GIF and AVIF, up to 50 files of 25 MB and 50 megapixels each.

Everything runs in your browser and nothing is uploaded. There is no web-address field: an image from another site would make the browser refuse to read the resized pixels back.

Size

Presets

A file already smaller than the target keeps its own size.

High-quality smoothing, with large reductions stepped down in halves. Best for photos.

Output

GIF and AVIF cannot be written from a canvas; each row says which format was used.
Applies to files saved as JPEG or WebP.

Re-encoding drops EXIF, GPS, XMP and colour-profile metadata, and wide-gamut (Display P3) photos may shift slightly in colour.

About This Tool

Image Resizer – exact dimensions for one photo or a whole batch

This image resizer changes the pixel dimensions of JPEG, PNG, WebP, GIF and AVIF files right in your browser. You describe the size you need once, as a percentage, a width, a height, a longest edge or an exact box, and the same recipe is applied to every file you drop in. Each image is decoded, drawn onto a canvas and re-encoded on your own device, so you can resize images without uploading them anywhere, and the batch can be downloaded file by file or as one ZIP archive.

Five ways to describe the size

Percentage scales both sides together, so 50 % of a 1001 × 667 image is 501 × 334. Width and Height fix one side and let the other follow the aspect ratio: a 4032 × 3024 phone photo resized to a width of 1200 becomes 1200 × 900. Longest edge is the one to use for a mixed batch of portrait and landscape shots, because the longer side always lands on your number. Exact size asks for a precise box and then lets you decide what happens when the photo is a different shape.

Whatever you type is hit exactly. Only the derived side is rounded, and it is always calculated from the original ratio rather than from an already-rounded figure, so a batch never drifts by a pixel.

Fit inside, pad, fill and crop, or stretch

Take a 3000 × 2000 photo and a 1080 × 1080 square target. Fit inside keeps the whole picture and returns 1080 × 720, the largest copy that fits the box. Pad returns exactly 1080 × 1080 with the picture centred and 180 px bands above and below in a colour of your choice, or transparency for PNG and WebP. Fill and crop scales the photo until it covers the square and trims the sides, keeping a 2000 × 2000 region of the original; the 9-point anchor decides whether the left, centre or right survives. Stretch forces the size by distorting the picture, here squashing it horizontally by 33.3 %. The live preview draws each of these before anything is processed, including the parts a crop will cut away.

Enlarging cannot add detail
Scaling up is allowed, but interpolation only blends the pixels that already exist, so an enlarged photo looks soft. The “Don’t enlarge smaller images” switch keeps small files at their own size in a batch. For pixel art, choose Pixelated resampling and a whole-number scale such as 200 % or 300 %, so every source pixel becomes an even square block.

Resizing for print: units and DPI

Switch the unit to millimetres, centimetres or inches and a DPI field appears. The pixel count is round(inches × DPI), where inches are mm ÷ 25.4 or cm ÷ 2.54. A print size is only useful if the file says how it should print, so the DPI is also written into the header: the JFIF density for JPEG and a pHYs chunk for PNG. Word, Photoshop and print shops then open it at the physical size you asked for instead of assuming 72 DPI. WebP has no widely supported DPI field, so choose JPEG or PNG for print.

PaperSizePixels at 150 DPIPixels at 300 DPI
A4210 × 297 mm1240 × 17542480 × 3508
US Letter8.5 × 11 in1275 × 16502550 × 3300
Photo 4 × 64 × 6 in600 × 9001200 × 1800
Photo 5 × 75 × 7 in750 × 10501500 × 2100

Batch limits and output formats

A batch holds up to 50 files of up to 25 MB and 50 megapixels each. Files are processed one at a time and released straight afterwards, so a large batch does not hold fifty decoded photos in memory. Outputs are capped at about 16.7 megapixels and 16,384 px per edge, because some mobile browsers silently return a blank canvas beyond that. When a target is too large, the tool refuses it and names the largest size it can produce at the same aspect ratio, rather than quietly delivering something smaller.

Output can match the original format or be converted to JPEG, PNG or WebP. A canvas cannot write GIF or AVIF, so those become PNG or JPEG, and the results table says which was used. Transparent areas sent to JPEG are flattened onto a matte colour you pick. Canvas re-encoding also drops EXIF, GPS and colour-profile metadata, after first applying the EXIF rotation so phone photos stay upright.

Need a smaller file rather than smaller dimensions?
Resizing changes how many pixels an image has. If the goal is a lighter upload at the same size, the Social Image Compressor tunes the encoder quality instead. To frame a single photo by hand, the Social Post Image Cropper lets you place the crop yourself.

Frequently Asked Questions

Is the Image Resizer free?

Yes, Image Resizer is totally free :)

Can I use the Image Resizer offline?

Yes, you can install the webapp as PWA.

Is it safe to use Image Resizer?

Yes, any data related to Image Resizer only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does this image resizer work, and is my image uploaded?

Nothing is uploaded. Each file is decoded, drawn onto a canvas at the new size and re-encoded by your own browser, so the tool keeps working with the network disconnected. That is also why there is no field for an image URL: drawing an image from another website taints the canvas, and the browser then refuses to hand back the resized pixels.

Fit inside, Pad, Fill and crop or Stretch: which should I use?

Fit inside keeps the whole picture and the aspect ratio, so the output can be smaller than the box on one side. Pad gives the exact box size by adding borders in a colour you choose (or transparency). Fill and crop gives the exact box size by trimming the overflow, with the anchor choosing which part survives. Stretch hits the exact size by distorting the picture, which suits textures and backgrounds but not faces.

Why does my enlarged image look blurry, and when should I use Pixelated?

Enlarging has to invent pixels between the real ones, and smooth interpolation fills them with blends, so edges go soft. No resizer can add detail that was never captured. Pixelated (nearest neighbour) copies each source pixel into a square block instead, which is right for pixel art, icons and sprites, and looks cleanest at whole-number scales such as 200 % or 300 %.

Does changing the DPI change the pixels?

Only when you type a print size. In mm, cm or inches the DPI decides how many pixels that size needs (A4 at 300 DPI is 2480 × 3508). The DPI is then written into the file header, as the JFIF density for JPEG and a pHYs chunk for PNG, so Word or Photoshop opens it at the right physical size. WebP has no widely read DPI field, so nothing is written for it.

Why is my resized file bigger than the original?

Enlarging adds pixels, and switching from JPEG to PNG swaps lossy compression for lossless, which can multiply the size several times over. A high JPEG quality setting on an already-compressed photo can also add bytes. The results table states any growth plainly; pick JPEG or WebP and a lower quality if the file size matters.

What happens to EXIF, GPS data and colour profiles?

They are dropped, because a canvas re-encode writes pixels and nothing else. The EXIF rotation is applied to the pixels first, so phone photos stay upright. Wide-gamut Display P3 photos can shift slightly in colour once their profile is gone.