This register records exactly one declared alternative to OpenWPM: Englehardt & Narayanan — 1-Million-Site Measurement, which reads ACTIVE at the last field check. OpenWPM itself reads ACTIVE. Every row in the table below is judged by the same rubric, from the same sweep, on the same fields — this page ranks nothing and recommends nothing, because a register that has measured no population is in no position to.
Every row below is judged by the same rule as OpenWPM itself, from the
same field check. Supersession is only printed where a project or its
author says so — this register does not infer that one tool replaces
another because it is newer.
Read the state column with the licence column. A permissively licensed
project that stopped shipping is not safer than a copyleft one that did
not.
What OpenWPM does, so you know what you are replacing
The web-measurement platform behind a large share of the papers in this section: an instrumented browser plus a crawl harness plus a schema for the data it collects.
A substitute has to do that job, not merely occupy the same category. It is research infrastructure, and its operational assumptions — scale, storage, browser version pinning — are those of a research crawl rather than a production scraper. Its licence resolves to NOASSERTION and is worth reading directly.
How this register decides what counts as an alternative
Englehardt & Narayanan — 1-Million-Site Measurement is recorded as a substitute for the same job. The alternative relation is symmetric and carries no ordering at all: it says these things answer the same question, and it says nothing whatsoever about which answers it better.
Nothing on this page is a ranking, a score or a recommendation, and nothing on it is a detection-test result — no entry in this register has been run against any anti-bot system by this register. What the table gives you is four measured columns and one derived one, applied identically to every row.
How to read the comparison above
Every candidate reads ACTIVE or SEMI, so the choice here is genuinely about fit rather than about survival. Compare the release column rather than the push column: a project that pushes constantly and tags rarely asks you to depend on a branch, which is a different commitment from depending on a version.
Every entry in the table declares a licence, which is less common in this catalogue than it should be — the entries that declare none are grouped separately. Read the licence column beside the state column rather than after it: a permissively licensed project that stopped shipping is not a safer dependency than a copyleft one that did not.
Why ACTIVE: No repository. The link check returned 200 at 2026-08-14T09:12:00Z, and 200–399 is ACTIVE for a non-repository entry.
Field
Value at this printing
http_status
200
fetched_at
2026-08-14T09:12:00Z
rubric_edition
2nd, in force
Endpoint: HEAD https://webtransparency.cs.princeton.edu/webcensus/
No repository, so there is no API field to re-read from a browser. A cross-origin liveness check has to be made server-side; this entry's status comes from the register's own sweep.
Answered from the same fields the table above prints, and from no other source.
What is the best alternative to OpenWPM?
This register does not answer that, because it publishes no ranking and has tested no tool to rank. What it can tell you is which candidates are still shipping: Englehardt & Narayanan — 1-Million-Site Measurement. The rest of the decision is fit, licence and how much of your own stack you are prepared to change.
Because a ranking would be an opinion wearing a number's clothes. Every figure on this site is a date, a count, an SPDX identifier or an HTTP status you can re-fetch from the endpoint named beside it, and there is no honest way to compress those into an ordering without inventing weights nobody published. The rubric sets states; it does not rate them against each other.
Where does the alternatives data for OpenWPM come from?
From declared edges in the register itself, never inferred. Each edge is stored once and reversed at build time, and every field in the table is read from the same sweep that produced the rest of the catalogue. The whole set is downloadable as CC0 JSON and CSV, including the supersedes, superseded_by and alternative_to columns.
The literature in section 05 keeps arriving at the same finding from different directions: what gets a browser caught is not rarity but contradiction between its own signals. Donut Browser is built around that result rather than around the older one — the Wayfern fork spoofs at engine level over CDP so the values a page reads are coherent with each other, and a pre-launch gate refuses to start a profile whose proxy geography disagrees with its fingerprint.