Best Free Image Tools Online - Compress, Resize, Convert & HEIC

The four free image tools most people need are a compressor, a resizer, a format converter, and a HEIC-to-JPG converter. Toolstik has all four, and each runs entirely in your browser: the Image Compressor, Image Resizer, Image Converter, and HEIC to JPG. This guide explains what each one does (and doesn't do), how to chain them, and which step-by-step guide to read next.

Which tool do you need?

*AVIF input works only when your browser can decode AVIF.

All four tools accept multiple files up to 25 MB each. A single result downloads directly, and several download as a ZIP. Every tool also has a Reset button to clear the queue. You'll find them grouped on the image tools category page.

Image Compressor

The Image Compressor reduces file size by re-encoding images at a lower quality and, optionally, a smaller width.

Controls:

• Quality slider, 10-100%, default 80%. Values below 30% are treated as 30%.
• Max width (px), default 2048. Wider images are scaled down with their aspect ratio kept. 0 keeps the original size. It never enlarges.
• Compress images starts the batch. Download or Download ZIP (compressed-images.zip) saves the results.

What makes it different: it tries more than one format and keeps whichever is smallest. JPGs stay JPG. PNGs can become JPG or WebP. If your chosen quality doesn't beat the original size, it steps down through 65%, 50%, 40%, and 30%. If nothing beats the original, you get the original back, labelled already optimized, so it never returns a bigger file. The result summary shows original size, compressed size, and savings for each file.

Watch out for: transparency. Images are drawn onto white before encoding, so transparent logos and icons come back with a white background.

Guide: How to compress images without losing quality

Image Resizer

The Image Resizer changes pixel dimensions without stretching or cropping.

Controls:

• Max width (px, 0 = ignore), default 1200.
• Max height (px, 0 = ignore), default 0.
• Resize images, then Download or Download ZIP (resized-images.zip).

How the boxes work: fill in one and the other side follows the aspect ratio, so 4032×3024 at width 1600 becomes 1600×1200. Fill in both and the image fits inside that box: 4032×3024 inside 1080×1080 becomes 1080×810. With one box the image can be enlarged. With both it only shrinks.

Watch out for: WebP input is saved as JPG, and the default width of 1200 will upscale smaller images. PNGs stay PNG with transparency intact.

Guide: How to resize images online

Image Converter

The Image Converter switches formats without changing dimensions.

Controls:

• Output format: WebP (default), JPG, or PNG.
• Quality, 10-100%, default 85%. It's disabled for PNG, which is lossless.
• Convert images, then Download or Download ZIP (converted-images.zip).

What it's good for: making WebP versions of website images, turning WebP or AVIF downloads into JPG for apps that won't open them, and creating lossless PNG working copies.

Watch out for: WebP and JPG output fill transparent areas with white, so choose PNG to keep transparency. If your browser can't encode WebP, the tool falls back to JPG, so check the file extension. It reads AVIF but doesn't write it.

Guides: How to convert images to WebP, WebP vs JPEG, and JPG vs PNG vs WebP vs AVIF

HEIC to JPG

HEIC to JPG turns iPhone photos into JPGs that every app, website, and Windows PC can open.

Controls:

• JPEG quality, 50-100%, default 85%.
• Convert to JPG, then Download JPG or Download ZIP (heic-converted.zip).

How it works: it decodes HEIC with the heic2any library in your browser, which works even on Windows PCs without Microsoft's HEIF and HEVC extensions. IMG_0421.HEIC becomes IMG_0421.jpg at the same dimensions.

Watch out for: decoding is heavy work. On older or low-memory devices, convert 10-20 photos at a time. Multi-image HEIC files (such as bursts) produce one JPG from the first image. Don't rely on EXIF metadata like location carrying over.

Guides: Convert HEIC to JPG on Mac, which covers Finder, Preview, and Photos, and convert HEIC to JPG on Windows, which covers the Photos app, codecs, and why HEIC won't open.

Workflows that chain the tools

The tools are designed to work one after another. Order matters, because each step decides what format the next one receives.

iPhone photos to a fast web page

1. HEIC to JPG at 85%. Your 4032×3024 photos become JPGs.
2. Image Resizer with width 1600 gives 1600×1200 JPGs.
3. Image Converter set to WebP at around 80% gives .webp files for your site.

Convert to WebP last, because the resizer saves WebP input as JPG.

Product photos for an online store

1. Check your platform's recommended dimensions, which change over time.
2. Image Compressor with Max width (px) set to that size and quality at 80-85%. Resizing and compression happen in one pass.
3. Check the per-file savings. Anything marked "already optimized" was already as small as the tool could make it.

Email attachments under a size limit

1. iPhone photos go through HEIC to JPG first.
2. Image Compressor with quality at 75% and max width 1600 gives 1600×1200 for 4:3 photos.
3. Send JPGs, not WebP. Some email clients and recipients still can't preview WebP.

Transparent logo for a website

1. Image Resizer with both boxes set, for example 512 and 512. PNG stays PNG and keeps its transparency.
2. Skip the compressor, because it would add a white background. If you need a smaller transparent file, use a dedicated optimizer such as Squoosh.

Photos into a PDF document

1. Resize or compress the images first so the PDF stays a reasonable size.
2. Combine them with JPG to PDF. Our guide on converting JPG to PDF covers page size and margins.
3. Going the other way, PDF to JPG exports pages as images. See how to convert PDF to JPG.

Picking a format

A short version of our four-format comparison:

If you're only deciding between WebP and JPEG for your site, the WebP vs JPEG comparison covers it.

Settings cheat sheet

These are starting points. Check the results at the size they'll be displayed.

• Web photos: compress at 70-80% with max width 1600-2048.
• Text-heavy screenshots: keep as PNG, or use 85-90% quality.
• HEIC conversion: the default of 85% is a good balance; use 90% or higher for archiving.
• WebP conversion: 80-85% for photos.
• High-density screens: use an image width of twice the displayed CSS width.

Common problems across all tools

• A dropped file doesn't appear in the list. It's over 25 MB or in an unsupported format, and the tools skip those files.
• The output has a different extension. That's expected: the compressor picks the smallest format, the resizer saves WebP as JPG, and the converter falls back to JPG when WebP encoding isn't available.
• Transparency disappeared. Only PNG output keeps it in Toolstik's tools: the resizer with PNG input, or the converter with PNG output.
• Quality got worse after several passes. Every lossy save loses detail. Work from your originals, and run each step once.
• AVIF won't open. Your browser can't decode it. Check caniuse.com/avif or update your browser.

When other tools are a better fit

Toolstik is built for quick, private batch jobs. Other tools are better for some tasks:

• Squoosh: side-by-side visual tuning, AVIF output, and transparent WebP, one image at a time.
• macOS Finder, Preview, and Photos: built-in HEIC conversion and resizing on a Mac. The Mac HEIC guide shows each method.
• Windows Photos and Paint: single-photo conversion once the HEIF and HEVC extensions are installed. The Windows HEIC guide explains the codecs.
• iPhone settings: Settings > Camera > Formats > Most Compatible makes the camera save JPG in the first place.
• Your CMS or image CDN: if it already resizes and converts uploads, give it high-quality originals and skip manual steps.
• Full photo editors: for cropping, retouching, and color correction, which Toolstik doesn't do.

Don't forget the file name

Search engines and screen readers can't see your image, but they can read its file name and alt text. Rename IMG_0421.jpg to something descriptive, like blue-ceramic-mug-front.jpg, before uploading. The rules for readable, lowercase, hyphenated names are the same as for URLs, which our guide to creating SEO-friendly URL slugs covers.

Privacy

Every image tool on Toolstik processes files locally. The compressor, resizer, and converter use your browser's built-in canvas, and HEIC decoding uses heic2any in the page. Nothing is uploaded to Toolstik servers, which makes the tools safe for client work, private photos, and screenshots with sensitive details.

Looking beyond images? See the free PDF tools or the full free online tools hub, or browse all tools.