Ka-Block! is a content blocker for Safari that prevents ads and tracking scripts from slowing down web pages you visit.

Many sites use third-party scripts to track your behavior across the web, causing pages to load slowly and draining your Mac’s battery. Blocking these scripts dramatically improves page load time, data usage, and battery life.

- Fast, curated filter list
- Open source
- Also available for Safari on iPhone

Protecting privacy and performance on the web is important. We hope you enjoy Ka-Block!

What’s New

Version 3.3

Updates to the filter list.

Ratings and Reviews

3.3 out of 5
163 Ratings

163 Ratings

Got blocked ,

Love it ……but , too effective ?

This works as advertised and quietly behind the scenes . Solid ad blocker that just plain works and very effectively .
Unfortunatly its a little too effective . Now I cant log in to access a certain member website that I need access too . I thought the site was just down , but it turns out the KaBlock ad was preventing me to get past the log in screen . Uninstalled KaBlock, and had no problems .
Love this ad Blocker, but sadly cant use it. If it only had a user friendly way to bypass blocking on certain websites that didnt need blocking, it would be perfect .

badkitty_ ,

Works great as long as you remember to enable Safari content blocking!

I thought this wasn't working and that it wasn't removing the dreaded AdChoice ads. I was mistaken! It actually works great as long as you remember to enable Safari Content Blocking in Safari Preferences.

It also respects your privacy! It clearly states it does not have permission to read or transmit content from any webpages. That is definitely not the case with all ad blockers! Some can read your passwords and credit card info and will tell you that (click the fine print next to your Safari extensions in Safari/Preferences/Extensions

Keep up the great work, guys!

Aspierce1 ,

The most simple and effective ad blocker for Safari!

I have been using Kablock for over a year now and it is by far my go-to choice for Safari and iOS. It effectively blocks ads without breaking websites (or even having websites detect you're using an adblocker) without ever requiring the user to do anything beyond install the extension. My only wish is if the developers provided an extension for Firefox too so I could use it on my Windows laptop for work.


Negative Code, LLC
4 MB

macOS 10.13 or later, 64-bit processor



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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