ooni.org

OONI is a global community project that measures internet censorship around the world. It runs two main tools: OONI Probe, which you install to test whether websites and apps are blocked and to measure network speed and performance, and OONI Explorer, a public interface for tracking censorship worldwide in near real time. The project publishes its measurements as an open dataset — millions of measurements collected from more than 200 countries since 2012 — which makes it useful if you want to check whether a specific site or service is reachable from a given network, or if you need evidence for research, journalism, or advocacy.

What OONI actually does

OONI collects data by having volunteers run tests from their own networks. Each test produces a measurement: a record of what happened when a specific site, app, or service was accessed from a particular location at a particular time. Those measurements are then aggregated and published.

Two components do the work:

• OONI Probe — the client software you run to perform the tests. According to OONI's own description, it is used to "test the blocking of websites and apps" and to "measure the speed and performance of your network."
• OONI Explorer — the web interface for browsing the resulting data. OONI describes it as a way to "track internet censorship worldwide in near real-time," and it hosts what the project calls "the world's largest open dataset on internet censorship."

The data behind it

Because the dataset is open, you are not limited to reading OONI's own summaries — you can look at the underlying measurements for a country, a time window, or a specific service.

What the data is used for

OONI's published research shows the range of questions the measurements can answer. Recent examples listed on the site include:

• Italy blocks reproductive health websites — Women on Web (WoW) and Women Help Women (WHW)
• Collateral damage of IP-based blocking during LALIGA football streaming in Spain — evidence drawn from OONI measurements
• Abortion access denied — an investigation into global censorship of Women on Web
• How internet censorship impacts the women's rights movement in Iran — insights from OONI data and activist interviews
• Throttling of social media in Türkiye during protests — an analysis of OONI data

These illustrate the two common uses: documenting that a block or throttle is happening, and connecting that technical finding to its social or legal consequences.

When OONI is the right tool

OONI fits situations where you need network-level evidence of blocking or throttling from real vantage points, rather than a single test from one machine. It is a good match if you are:

• A researcher or journalist who needs citable, timestamped measurements
• An advocate documenting censorship of a specific site or category of sites
• Someone who wants to contribute measurements from your own network by running OONI Probe

It is less suited to questions OONI does not claim to answer — for example, why a block was imposed, or whether a service is down for reasons unrelated to censorship. OONI measures interference; interpreting cause and intent is a separate step, which is why its research posts pair measurements with context and interviews.

How to start

1. To contribute data: install OONI Probe and run the tests. The site's "Get Involved" section is the entry point.
2. To look at existing data: open OONI Explorer and browse by country or service.
3. To understand the methodology: OONI publishes its testing methodologies, plus a glossary and FAQ for terminology.

If you only need a quick answer to "is this site blocked where I am," running OONI Probe from that network and then checking the result in OONI Explorer covers both the test and the comparison against other measurements.

OONI data can show you whether specific websites and apps are blocked, throttled, or otherwise interfered with on the networks where volunteers ran tests — and it can show this across more than 200 countries going back to 2012. What it cannot do is give you a single, definitive verdict on "how censored" a country is. Each measurement reflects one test on one network at one moment, so the data is strongest when you read many measurements together and weakest when you treat a single result as proof.

What OONI measures

OONI (Open Observatory of Network Interference) is a global community project that measures internet censorship. Its two main tools serve different purposes:

• OONI Probe — the client you install to run tests on your own network. It tests the blocking of websites and apps and measures network speed and performance.
• OONI Explorer — the public interface for browsing the resulting dataset, described by OONI as the world's largest open dataset on internet censorship, with millions of measurements collected from more than 200 countries since 2012.

The kinds of interference the data can surface include:

The IP-based blocking case is worth understanding because it produces misleading-looking results. OONI's own research on LALIGA football streaming in Spain documents how blocking aimed at one target can cause collateral damage to unrelated services that happen to share infrastructure. If you see a cluster of unrelated failures, shared hosting or a shared IP range is a plausible explanation before you conclude that each site was individually targeted.

How to read a result responsibly

Treat OONI data as evidence about networks, not as a country-level score.

1. Check how many measurements support the claim. One blocked result on one network is an anecdote. A consistent pattern across many networks, ISPs, and time periods is a finding.
2. Check where the measurements came from. OONI Probe runs on volunteers' devices, so coverage is uneven. A country with few volunteers will have thin data, and that thinness is not itself evidence of anything.
3. Check the local network conditions. A failure can come from a misconfigured router, a captive portal, a local outage, or a filtering middlebox — not necessarily a national censorship system.
4. Look for the mechanism, not just the outcome. Distinguishing a DNS block from an IP block from throttling changes what you can conclude about who is interfering and how.
5. Use OONI's own explanatory material. The project publishes its testing methodologies, a FAQ, and a glossary specifically so that people interpreting the data don't have to guess at definitions.

What the data is good for

• Tracking change over time. Because measurements accumulate continuously, you can compare a service's reachability before, during, and after a politically significant event.
• Documenting specific cases. OONI's research blog covers concrete findings — for example, work on the blocking of reproductive health websites such as Women on Web and Women Help Women, on censorship of abortion-related resources globally, and on social media throttling in Türkiye during protests.
• Supporting journalism and advocacy with citable measurements. The dataset is open, so a claim can be traced back to the underlying tests.
• Comparing networks within a country. Differences between ISPs in the same country are often more informative than a national average.

What the data cannot tell you

• It cannot tell you intent. A measurement shows interference occurred; it does not identify who caused it or why.
• It cannot tell you the full extent of censorship. Tests only cover the specific sites and apps in the test list. Censorship of something not tested will not appear.
• It cannot give you uniform geographic coverage. Volunteer distribution is uneven, so absence of measurements is not absence of censorship.
• It cannot isolate a single cause from a single result. Local network problems and censorship can produce similar-looking failures.

Practical rule of thumb

If you want to cite OONI data, state three things alongside the finding: how many measurements support it, which networks and locations they came from, and over what time period. If you can't state those, you have a lead worth investigating rather than a conclusion worth publishing.

The most direct way to contribute is to install OONI Probe and run tests on your own network, then let the measurements flow into OONI's open dataset. OONI (Open Observatory of Network Interference) describes itself as a global community measuring internet censorship around the world, and its site organizes participation around three entry points: running OONI Probe, exploring OONI data, and following research. If you want to do more than observe, start with Probe and build outward from there.

Run OONI Probe to contribute measurements

OONI Probe is the tool the project positions as the front door for contributors. According to the site, it lets you:

• Test the blocking of websites and apps
• Measure the speed and performance of your network

Each test run produces measurements that feed into what OONI calls "the world's largest open dataset on internet censorship," with millions of measurements collected from more than 200 countries since 2012. That dataset is the reason individual test runs matter — your network becomes one more observation point.

Practical steps:

1. Install OONI Probe on a device connected to the network you want to test.
2. Run the built-in tests (website and app blocking, plus network performance).
3. Let the results upload so they join the public dataset.
4. Re-run tests periodically, since censorship conditions change over time.

A useful habit: test the same set of sites or apps across different networks (home, mobile data, work) and compare. Differences between networks in the same country are often where the interesting findings are.

Explore and reuse OONI data

If you'd rather analyze than measure, OONI Explorer is the site's interface to the open dataset. The homepage frames it as a way to "explore the world's largest open dataset on internet censorship" and to track censorship worldwide in near real-time.

This path suits you if you want to:

• Check whether a specific site or service is blocked in a given country
• Follow censorship events as they develop
• Pull data into your own research or reporting

The site also links to a glossary and a FAQ, which are worth reading before interpreting measurements — knowing what a measurement does and doesn't show prevents overclaiming.

Follow OONI's research and blog

OONI publishes findings and methodology through its Research and Blog sections. Recent examples from the site show the range of topics:

Reading these gives you a sense of what OONI data can support — and the site's testing methodologies page explains how measurements are produced, which is useful if you plan to cite or build on them.

Reach the community through Get Involved and Contact

The site has dedicated Get Involved and Contact sections. These are the channels for asking about contribution paths, research collaboration, or community work that isn't covered by simply running Probe. If your interest is organizing, translating, or partnering rather than measuring, that's where to start.

A realistic path

A practical sequence for a new contributor:

1. Run OONI Probe on your own network and let results upload.
2. Read the FAQ and glossary so you understand what you're contributing.
3. Use OONI Explorer to see how your measurements sit alongside others.
4. Follow Research and Blog to learn what the community does with the data.
5. Use Get Involved or Contact when you want to go beyond testing.

The measurement itself is the contribution — everything else builds on having that data in the open dataset.

OONI Probe is a free app from the Open Observatory of Network Interference (OONI) that tests whether websites and apps are blocked on your network, and also measures network speed and performance. Install it on your device, run the built-in tests, and your measurements are uploaded to OONI's open dataset, where you can review them alongside results from more than 200 countries collected since 2012. It's the right tool if you want evidence about what your network blocks rather than a general impression — but it tests specific categories of sites and services, not everything you might care about.

What OONI Probe actually measures

OONI describes two broad jobs for the app:

• Test the blocking of websites and apps. This is the censorship-detection side: you run tests against lists of sites and services, and the app records whether they were reachable and how the connection behaved.
• Measure the speed and performance of your network. This is the network-quality side, useful for separating "this site is blocked" from "my connection is just slow or unstable."

The distinction matters when you interpret results. A failed connection is not automatically censorship — it can also come from a down server, a misconfigured network, or transient problems. OONI's methodology pages exist precisely because reading these measurements correctly takes some care.

Installing and running a test

The general flow is the same on any supported device:

1. Install OONI Probe from your platform's app store. OONI publishes the app for common mobile and desktop platforms; use the official listing rather than a third-party mirror.
2. Open the app and run a test. OONI Probe ships with a set of test categories you can launch individually or as a group. Pick the category that matches your question — for example, website reachability if you want to know whether specific sites load.
3. Let the test finish and upload. Measurements are sent to OONI's servers, which is what makes them part of the public dataset. If you don't want your results published, don't run the tests — the upload is the point of the tool, not an optional extra.
4. Note what you tested and when. Censorship is often intermittent and event-driven, so the date and the specific test matter as much as the result.

A practical habit: run the same test more than once, ideally on different days. A single run tells you what happened once; a series tells you whether a block is consistent.

Reading your results and the global picture

Your own measurements are most useful when compared against something. OONI Explorer is the companion tool — it's described as the world's largest open dataset on internet censorship, with millions of measurements from more than 200 countries since 2012, and it lets you track censorship worldwide in near real time.

Use it in two directions:

• Check your own network. Find measurements from your country and network to see whether what you observed matches what others observed.
• Check the global picture. OONI's research blog shows what this data looks like when analyzed — for example, posts on IP-based blocking during LALIGA football streaming in Spain, on blocks of reproductive health websites in Italy, and on throttling of social media in Türkiye during protests. These are useful models for what a well-supported censorship finding looks like, as opposed to a single failed page load.

If you're new to the terminology, OONI publishes a glossary and a FAQ alongside the data explorer; both are worth skimming before you draw conclusions from a result you don't recognize.

Common pitfalls

• Treating one failure as proof of blocking. Cross-check with repeated runs and with OONI Explorer data from your network.
• Forgetting that tests are category-based. OONI Probe checks the sites and services in its test lists. A site outside those lists won't be covered unless it's added.
• Ignoring the upload. Results only become part of the public record once submitted; local-only testing limits what you and others can compare against.
• Assuming a slow result means censorship. That's why the performance tests exist — run them to rule out ordinary network problems.

Getting involved beyond testing

OONI frames itself as a global community effort, and the site has a "Get Involved" section for people who want to contribute beyond running tests — for instance by helping expand test lists or contributing to research. If your interest is ongoing monitoring of a specific network or region rather than a one-off check, that's the path to look at.

OONI Explorer is the public interface to the Open Observatory of Network Interference (OONI) dataset — described on ooni.org as "the world's largest open dataset on internet censorship," with millions of measurements collected from more than 200 countries since 2012. You use it when you want evidence about whether a specific site or app is blocked, throttled, or reachable in a given country, rather than a general claim that "the internet is censored there." It is a browsing and analysis tool, not a live test of your own connection — for that you run OONI Probe, which feeds the same dataset.

What OONI Explorer actually contains

Each record in Explorer comes from an OONI Probe measurement: a test run on a real network somewhere in the world. The dataset is built from two main test families referenced on the site:

• Website and app blocking tests — check whether specific sites or services are reachable, and classify anomalies (for example, signs of DNS tampering, TCP/IP blocking, or HTTP interference).
• Network performance tests — measure speed and performance of the network the probe ran on.

Because measurements are contributed by volunteers, coverage is uneven: some countries and time periods have dense data, others are sparse. Explorer shows you what exists, not a guaranteed sample of every network in a country.

How to look up censorship in a country or for a specific site

The workflow below matches how the dataset is organized. Exact button labels may change as the site is updated, so treat the steps as the sequence of filters rather than fixed pixel positions.

1. Open OONI Explorer from ooni.org (the "Explore OONI Data" entry point).
2. Choose your filter dimension. You can browse by:
   • Country — pick the country you care about.
   • Time range — narrow to the period you're investigating (useful for tying results to an event such as an election or protest).
   • Test type / measurement — restrict to website blocking, app blocking, or performance, depending on your question.
3. Read the results as measurements, not verdicts. A single anomalous measurement is a signal, not proof. Look for a pattern: the same site failing across many probes, on multiple networks, over a sustained window.
4. Open individual measurements to see the detail — which test ran, what the network returned, and how the result was classified (reachable, anomaly, confirmed block, etc.).
5. Cross-check against OONI's own reporting. The site's Research and Blog sections publish analyses that interpret the raw data, for example country-specific findings on blocked categories of sites or throttling during protests. Comparing your filter results with a published analysis helps you avoid misreading an isolated anomaly.

Reading the results without over-claiming

The most common mistake is treating one red result as a confirmed nationwide block. Keep these distinctions in mind:

Absence of measurements is not evidence of a free internet. It usually means too few volunteers ran OONI Probe on that network during that window.

Using findings for research, reporting, or advocacy

Explorer's value for a write-up or campaign comes from being specific and reproducible:

• Cite the scope: country, time range, test type, and number of measurements you looked at.
• Show the pattern, not one dot: reference multiple measurements rather than a single anomalous result.
• Link to the raw measurement so others can verify it.
• Pair data with context: OONI's blog analyses show how measurement data is combined with interviews and events (for example, work on censorship of specific services or throttling during protests). Following that model keeps your claim defensible.

If your goal is to add data rather than read it, install and run OONI Probe — its measurements become part of the same public dataset you're browsing in Explorer.