# DNS Medic

> Detects DNS blocks that break websites. Supports NextDNS, Pi-hole, and Control D. Groups domains by risk level and lets you allowlist them instantly.

Canonical page: [https://chrome-stats.com/d/dns-medic](https://chrome-stats.com/d/dns-medic)

## Overview

- **ID:** `dns-medic`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** jstoneky
- **Category:** privacy-security
- **Daily users:** 15
- **Weekly downloads:** 2
- **Rating:** 5.00 / 5 (1 ratings)
- **Version:** 3.2.5
- **Last updated:** 2026-04-12
- **First published:** 2026-03-28
- **Size:** 635 KB
- **Data as of:** 2026-09-09
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/dns-medic/)
- **Website:** [https://github.com/jstoneky/nextdns-medic](https://github.com/jstoneky/nextdns-medic)

## Description

The Problem
NextDNS, Pi-hole, and other DNS-level blockers work great for privacy, but they can cause subtle breakage on websites. A feature flag service gets blocked, and suddenly an inventory page won't load. An auth provider is blocked, and login silently fails. A payment processor is blocked, and checkout never completes. You reload the page six times wondering what's wrong, never knowing DNS was the culprit.

This extension makes that visible — and tells you exactly what's at stake.

How It Works
Monitors network errors on every tab using the browser's webRequest API
Identifies DNS-block signatures — certificate issuer failures, name resolution errors, and other patterns that indicate a DNS-level block (not a server error or timeout)
Classifies every blocked domain against a database of 492 known services across 13 categories, grouped by how likely they are to break site functionality:
🔴 High — Feature flags, authentication, payment processors, search APIs, core CDNs, CAPTCHA. These break sites.
🟡 Medium — Support chat, video players, maps, image CDNs, error monitoring, e-commerce. May affect functionality depending on the site.
🟢 Low — Pure analytics and advertising. Almost never affects how a site works.
Shows a functional impact badge on every blocked domain — so you know at a glance what breaks, not just that something broke
Attributes the block to a specific blocklist — works for both NextDNS (from the logs API) and Pi-hole v6 (via the gravity search API, with pretty names for 30+ common lists)
Confirms DNS routing — a live status chip in the header shows whether your browser is actually sending DNS through your selected provider (green = active, red = not routing)
Unknown domains fall back to Medium — worth reviewing, but not necessarily critical
Badge updates on the extension icon: count of blocked domains, red = high-risk detected

## Rankings

- #27,714 — Overall
- #108 — e-commerce
- #160 — medium
- #167 — risk
- #169 — payments
- #178 — captcha

## Permissions and access

### Permissions

- `webRequest`
- `tabs`
- `storage`
- `activeTab`
- `webNavigation`
- `<all_urls>`
- `https://raw.githubusercontent.com/jstoneky/nextdns-medic/*`
- `clipboardWrite`

## Safety

- **Risk impact:** Very high risk impact
- **Risk likelihood:** Moderate risk likelihood

### Analysis details

- Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
- This extension has low user count. Unpopular extensions may not be stable or safe.

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

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Source: [Chrome-Stats](https://chrome-stats.com/d/dns-medic)