How to block Character.AI

How to block Character.AI on every device

Character.AI is a roleplay chat platform with user-made AI characters, and one of the most-used AI apps among teenagers. Below: how to block Character.AI in the browser, on phones and tablets, on your home or school network, and on managed devices.

Start a free trial

AI blocker suite for browsers, desktop, and mobile

Chrome
Edge
Firefox
Safari
iOS
Android
macOS
Windows

Blocks prompts and AI apps
100% on-device processing

Character.AI

AI companions and roleplay

character.aiBlocked

2 hostnames in the Nullgen catalog

Every entry also covers its subdomains, so the Character.AI app and API are blocked too.

What Character.AI connects to

These are the hostnames Character.AI uses for its website, its apps, and its API. Each entry is matched as a suffix — blocking character.ai also blocks every subdomain of it — so the Character.AI app cannot slip through on a hostname that is not listed. Shared hosts that other products need are deliberately left out.

Hostnames blocked for Character.AI
Hostname	Role
character.ai	Main website
c.ai	App, API, or content host

Block Character.AI in the browser

Free: the Nullgen browser extension

The free extension blocks Character.AI and every other tool in the catalog in Chrome, Edge, Firefox, and Safari. It works on the page itself — no DNS change, no policy — and updates as the catalog grows.

Download Free Extension

Managed browsers: block the sites by policy

On a school or company fleet, push the hostnames as a browser policy so Character.AI is blocked even when someone uninstalls extensions. These snippets use the official Chrome, Edge, and Firefox policy names and the same hosts listed above.

Chrome and Edge — URLBlocklist

{
    "URLBlocklist": [
        "c.ai",
        "character.ai"
    ]
}

Firefox — policies.json

{
    "policies": {
        "WebsiteFilter": {
            "Block": [
                "*://c.ai/*",
                "*://*.c.ai/*",
                "*://character.ai/*",
                "*://*.character.ai/*"
            ]
        }
    }
}

Chrome and Edge treat a bare hostname as the host plus every subdomain. Firefox needs both the apex and the wildcard pattern.

Need every AI tool in one file, or a .reg or macOS profile?

Open the free policy generator

Block the Character.AI app on phones and tablets

Nullgen mobile app

The Nullgen app blocks Character.AI and 100+ other AI apps and sites on the whole device with an on-device filter — the app, the website, and the API, on any network, with no DNS server to run. Included with Nullgen Pro.

Download on the App Store

Coming soon

Without Nullgen: Screen Time on iPhone and iPad

1Open Settings → Screen Time → Content & Privacy Restrictions and turn restrictions on. This covers Character.AI in Safari and in apps that use Apple’s web filter.
2Under Web Content, choose Limit Adult Websites — the setting that lets you deny character.ai by name.
3Under Never Allow, add character.ai. Safari and apps that use Apple’s web filter will refuse it.
4To keep the Character.AI app off the device entirely, delete it and set Installing Apps to Don’t Allow, or use Ask to Buy on a child’s Apple Account.

Without Nullgen: Family Link on Android

1Open Family Link, choose the child, then Controls → Content restrictions → Google Chrome — where Character.AI can be blocked by site.
2Choose Only allow approved sites, or add character.ai under Blocked sites.
3Under Controls → App limits, block the Character.AI app, or require approval for new installs from Google Play.

Block Character.AI on your home or school network

A DNS blocker such as Pi-hole, AdGuard Home, NextDNS, or pfBlockerNG blocks Character.AI for every device on the network — laptops, phones, consoles, and the Character.AI app — without installing anything on them. Subscribe to the Character.AI file from the public blocklist, or paste the rules directly.

Subscribe to the Character.AI list

Every vendor, one list — on GitHub

AdGuard Home, uBlock Origin, and Brave rules

||c.ai^
||character.ai^

DNS blocking cannot see inside a VPN or a phone on mobile data. For a block that follows the device, use the Nullgen apps or an MDM profile.

Block Character.AI on managed devices

Schools and companies can block Character.AI on every managed iPhone, iPad, laptop, and Chromebook from the MDM they already run — Intune, Jamf, Kandji, or Google Workspace — with per-person policies and an approval flow for legitimate use. Nullgen Pro provides the profiles and the dashboard; these guides walk through the setup.

Start a free trial

Questions about blocking Character.AI

Does the free Nullgen extension block Character.AI?
Yes. The free extension blocks prompts on Character.AI and every other AI tool in the catalog in Chrome, Edge, Firefox, and Safari. It works on the page itself, so it needs no policy and no DNS change.
Will blocking Character.AI break other websites?
No. Every hostname on this page belongs to Character.AI alone. Shared websites that other products depend on are never on the list — which is also why AI features built into those products stay reachable.
Can someone get around a Character.AI block?
A browser-only block can be bypassed with another browser or the Character.AI app, and a network block can be bypassed with a VPN or a phone on mobile data. A block on the device itself — the Nullgen apps, Screen Time, or an MDM profile — follows the device wherever it goes.
Does this block the Character.AI app, not just the website?
A DNS or device-level block does. The app talks to the same hostnames listed above, and every entry covers its subdomains, so the app cannot slip through on a hostname that is not listed. A browser policy or extension only covers the browser.
What happens when Character.AI adds a new hostname?
The catalog is updated as vendors change, and the Nullgen apps, the extension, and the public blocklist all read from it, so a new hostname reaches every device without anyone editing a list by hand.

More companion apps

Browse all 100+ AI tools

Block Character.AI today

Start with the free browser extension. Add Nullgen Pro when you need the Character.AI app blocked on phones, tablets, and desktops, with approvals for the people who really need it.

Download Free Extension Explore plans