> For the complete documentation index, see [llms.txt](https://docs.ipcheck.ing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ipcheck.ing/knowledge-base/network-tests/censorship-check.md).

# Censorship Check

## What it does

**Censorship Check** is one of the Advanced Tools. Give it a website and it answers two questions:

1. **Where has this site been blocked or interfered with recently?** This part uses open data from **OONI** — a global volunteer network whose members run measurement software from their own connections and publish the results. The tool looks at the past **30 days**.
2. **What happens right now?** This part sends live requests to the site from probes in the countries you pick, using the Globalping probe network.

The first part is history from real users. The second part is a fresh look you control.

## How to run it

{% stepper %}
{% step %}

### Enter the site

Type a URL or a domain name in the box and press the play button. You can enter `example.com` or the full address — both work.
{% endstep %}

{% step %}

### Read the 30-day summary

A banner sums up what OONI observed. If any countries were flagged, a list appears under it with the date range of the data.
{% endstep %}

{% step %}

### Optionally run a realtime test

Below the history is a **Realtime Test** panel. Tick countries in the left picker — the ready-made sections are **Flagged countries** (taken from the history above), **Heavily-censored countries** and **Usually-open countries**, followed by the full continent list. You can select up to **15**. Press **Run Verify**.
{% endstep %}
{% endstepper %}

## Reading your results

### The 30-day history

Each flagged country gets a row with a badge, the share of measurements that looked abnormal, and how many measurements that share is based on.

| Badge                | What it means                                                                                                                             |
| -------------------- | ----------------------------------------------------------------------------------------------------------------------------------------- |
| Confirmed blocked    | OONI recognised a known block page. This is the strongest signal, and only appears in countries that serve identifiable block pages.      |
| Likely blocked       | A large share of measurements failed in a way typical of blocking. Countries that block by tampering rather than by block page land here. |
| Partial interference | A moderate share looked abnormal. Could be intermittent blocking — or normal noise. Treat as a hint, not a verdict.                       |

Countries that are **not** listed showed no clear signs of blocking in the data.

Each row also shows *how* the interference happened:

| Method             | What happened                                   |
| ------------------ | ----------------------------------------------- |
| DNS tampering      | The domain resolved to the wrong address        |
| TCP blocking       | The connection to the server was cut or refused |
| Connection failure | The request could not complete                  |
| Content tampering  | The page that came back was not the real one    |

You may also see one of these instead of a list:

| Message                                                | What it means                                                                   |
| ------------------------------------------------------ | ------------------------------------------------------------------------------- |
| No clear signs of blocking across *n* countries        | Good news, and based on a decent sample                                         |
| Only *n* countries observed this website               | Too little data to conclude anything, even if nothing was flagged               |
| No measurements for this website in the past 30 days   | Nobody tested it. That is not the same as "not blocked" — run the realtime test |
| Historical observation data is temporarily unavailable | OONI's API did not answer. The realtime test below still works                  |

### The realtime test

Each row is one probe. Two probes run per country, so matching results from both are more trustworthy than one.

| Status      | Meaning                                   |
| ----------- | ----------------------------------------- |
| Green check | The probe's request to the site completed |
| Red cross   | The probe's request failed                |
| Spinner     | Still running                             |
| Dash        | No result from that country               |

{% hint style="warning" %}
The realtime panel deliberately gives you raw results, not a verdict. A failed request is a strong hint, not proof of censorship — the site itself may be down, overloaded, or refusing that probe.

Globalping probes mostly sit in **datacenter** networks. Some websites block datacenter traffic on their own, and a home connection in the same country may behave differently. Read the two panels together.
{% endhint %}

## Caveats worth remembering

* **The data is crowd-sourced.** OONI measurements come from volunteers. A country with few volunteers produces little data, and a site nobody tested produces none at all.
* **It can lag.** Measurements take time to be collected and published. A block that started today may not appear yet.
* **Blocking is often local.** One ISP, one city or one network may block a site while the rest of the country does not.
* **Not every anomaly is censorship.** Sites that serve different content by region, or that were simply down, can look abnormal in the data.

## What to do next

* A site will not open for *you* → [Can't Open a Website?](/knowledge-base/diagnose/cant-open-a-website.md)
* Check what your DNS returns for the domain, from several resolvers → [DNS Resolver](/knowledge-base/lookup-privacy/dns-resolver.md)
* Suspect your answers are being tampered with → [Is My DNS Hijacked or Polluted?](/knowledge-base/diagnose/is-my-dns-hijacked.md)
* See who runs the domain → [Whois Search](/knowledge-base/lookup-privacy/whois-search.md)


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