Which countries have the highest reported volumes of child sexual abuse material (CSAM) and how are reports measured?
Executive summary
Available reporting shows countries vary depending on the metric: the Netherlands and the United States repeatedly appear as high-volume hosts of CSAM when measured by hosting location or per‑capita hosting rates, while platform report tallies (e.g., NCMEC CyberTipline) show enormous volumes originating from or flagged by platforms that are not tied to a single country — NCMEC recorded more than 20 million reports and over 62 million files in recent annual data [1] [2]. Measurement methods differ: host‑location counts, platform/ESP reports to hotlines, and per‑capita rates based on hosting location or takedown records produce different country rankings and must be interpreted in context [3] [1] [4].
1. What the headline numbers actually measure — three different beasts
Data cited in public reporting are not uniform. The Internet Watch Foundation and other host‑location studies count URLs and servers where CSAM is stored; those analyses led to the finding that the U.S. hosted the largest share of CSAM URLs in some years [2]. Independent indices such as Childlight’s Into the Light calculate “reports per 10,000 people” based on INHOPE and NCMEC data to generate per‑capita hosting‑rate rankings that put the Netherlands far above other Western European countries (880.9 reports per 10,000 in 2024) [3] [4]. Separately, platform referral tallies — for example NCMEC’s CyberTipline receiving millions of reports from electronic service providers — count reports (and files) submitted by companies and the public; those figures reflect reporting behavior as much as raw hosting [1] [5].
2. Why rankings shift depending on method — hosting vs. reporting vs. detection
A country can appear high on a host‑location list because its infrastructure (data centers, cloud providers, internet exchange points) physically stores content even if the perpetrators or victims are elsewhere; Childlight points to the Netherlands’ role as a hosting and data‑centre hub as a likely factor in its high per‑capita rate [3]. Conversely, NCMEC’s CyberTipline volumes reflect referrals from global platforms and U.S. law (large U.S. companies reporting to NCMEC), producing huge report counts that are not synonymous with “originated in the U.S.” [1] [5]. INHOPE hotlines and Interpol add further layers: hotlines act on where content is hosted for takedown, while Interpol’s ICSE database supports victim identification across borders [6] [7].
3. The Netherlands and the United States: two different stories
Recent reporting and indices highlight the Netherlands as having an exceptionally high CSAM hosting rate in Western Europe per Childlight’s 2024 numbers — a rate Childlight links to the country’s hosting market and monitoring capacity rather than a simple conclusion about local offending [3]. Separately, the Internet Watch Foundation and reporting cited by MIT Technology Review found that the U.S. hosted the single largest share of CSAM URLs in a given year (about 30% at the end of March 2022), with researchers pointing to the U.S.’s concentration of data centres [2]. Both findings are supported by plausible structural explanations in the sources [3] [2].
4. Platform reporting overwhelms country tallies — scale and hidden bias
The volume of ESP referrals dwarfs many country‑level metrics: NCMEC’s CyberTipline received over 20 million reports and tens of millions of files in a single recent year, and NCMEC notes that more than 90% of some reports involved uploads originating outside the U.S. [1] [5]. Platform reporting practices, detection tools (including AI), and differing legal obligations — for example U.S. companies’ duty to report to NCMEC — skew comparisons across jurisdictions because some countries mandate reporting or have stronger detection partnerships [5] [8].
5. Measurement limitations — what the sources warn about
Researchers and hotspot reports caution that country‑level numbers are affected by proxies, anonymizers, hosting intermediaries, takedown speed, and variations in legal frameworks and hotline capacity; INHOPE and NCMEC data both note such caveats [9] [6]. Academic reviews also emphasize the lack of standardized metrics across platforms and services, making cross‑service and cross‑country comparisons unreliable without methodological harmonization [10].
6. Competing perspectives and policy implications
Advocates using per‑capita hosting rates (Childlight) argue that stronger regulation and enforcement in high‑hosting jurisdictions could substantially reduce global availability [3]. Others emphasize that the largest numerical burden sits with platforms and global reporting mechanisms like NCMEC and INHOPE, calling for better standardized metrics and improved detection/removal tools — including the ethical, privacy and technical debates around scanning proposals in the EU and elsewhere [1] [10] [11].
7. Bottom line for readers and policymakers
There is no single authoritative country ranking of “most CSAM” that applies across all definitions; the Netherlands and the U.S. both appear at the top under different methodologies, and giant platform referral counts (NCMEC’s 20M+ reports) reflect detection and reporting practices rather than clean geographic origin [3] [2] [1]. Any policy or public judgment must start by asking which measurement is being used — host location, per‑capita hosting rate, or platform referral counts — and heed the sources’ repeated caveats about proxies, reporting law, and inconsistent metrics [3] [10] [9].