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Exact-pixel Image Resizer

Resize Image to 300×300 (Tiny Square)

300×300 is a tiny square for email signatures and comment avatars. It is too small for print or Instagram. Keep a larger master.

Image Resizer

100% client-side · No uploads · Powered by HTML5 Canvas

Need the main tool? Image Resizer

Written by Safaat Rahman Siham, Founder & Developer at Convertify4u. Contact us.

Delivery size, not a master

Email signature reality

Outlook, Gmail, and Apple Mail all treat signature images differently. 300×300 at 72–96ppi is a common request so the photo does not explode to full width. If Mail.app still blows it up, the HTML width attribute is missing — fixing pixels here will not fix HTML.

Gravatar and comment thumbs

Gravatar serves multiple sizes from one upload, but some forums still ask for 300×300. Faces must be obvious at postage-stamp size. No fine text.

Do not upscale later

300×300 has very little detail. If you might need 1080×1080 for Instagram, keep the original and export 300×300 as a copy. This page is a shrinker.

File format

JPG for photos (small). PNG for logos. A 300×300 PNG logo is still tiny; a 300×300 photo JPG is usually under 50KB after a light compress.

How it works

  1. 1

    Start from a sharp square crop

    Downscaling a messy 12MP photo without cropping first makes a muddy 300px head.

  2. 2

    Export 300×300

    Pre-filled. JPG for faces.

  3. 3

    Insert with HTML width if needed

    In signatures, set width="300" (or smaller) so Outlook does not auto-scale.

Common use cases for 300×300

Email signatures

A face that stays small next to your title block.

Forum and CMS comment avatars

Fields that literally say 300×300.

Trust & technology

Exact 300 square

Not a 320×320 “close enough.”

Local

Signature photos stay on-device.

No watermark

Clean tiny thumbs.

Frequently asked questions

Image Resizer