About Local Image Optimizer
Local Image Optimizer is a free online tool for converting, compressing, and resizing images - built around one firm principle: your photos should never have to leave your device. Everything happens inside your own browser.
Why we built it
Most "free" online image tools work by uploading your files to a server you know nothing about. For a casual screenshot that may not matter, but personal photos carry hidden data - GPS coordinates, timestamps, device details - and handing them to an unknown server means trusting a stranger with all of it. We wanted a tool that delivers the same convenience without that trade-off.
How it works
The entire tool runs as client-side code using the browser's built-in Canvas API. When you drop in an image, it is read, processed, and exported entirely on your own computer. No file is ever transmitted over the network, there is no account to create, and nothing is stored once you close the tab. When you can't see a progress bar uploading your file, that's the point - there is no upload.
What you can do
- Convert between JPEG, PNG, WEBP, and AVIF, and convert iPhone HEIC photos so they open anywhere.
- Compress images with an adjustable quality control to shrink file sizes dramatically.
- Resize by exact dimensions for the web, email, social media, or print.
- Process up to ten images at once and batch-rename them with patterns.
- Strip EXIF metadata, add watermarks, rotate, and apply simple filters.
Who it's for
Photographers preparing galleries, developers optimising sites for Core Web Vitals, shop owners shrinking product photos, and everyday people who just want to email a few pictures without hitting the attachment limit. If it's an image and it's too big, in the wrong format, or carrying data you would rather not share, this tool is for you.
Alongside the tool we publish in-depth guides on image formats, compression, and web performance, and a step-by-step how-to for getting the most out of every setting.