How the figures are sourced and checked

Where the facts come from

We read each vendor's own pricing page. For every fact we keep the exact words the page used (the quote), the page's address and the date we read it. You can see all three on each tool's page. We do not copy numbers from review articles, and a fact that is not on the page is left blank, shown as a dash. A dash means the page did not say it plainly enough to verify, not that the feature is missing.

Extraction is automated: a program reads the page and proposes values. A second automatic check then confirms that each quote appears word for word in the page text we saved, and that the number is inside the quote. A value that fails that check is dropped.

The publish gate

A tool is published only if at least 6 of its 7 fields pass the check above: free monitors, fastest check, entry price, monitors on the entry plan, status page, alert channels and uptime SLA. Tools that fall short are not shown at all, which is why some well-known names are missing.

Free self-hosted tools have no price or plan, so they have their own gate: at least 4 sourced fields, including the licence and the minimum check interval, all quoted from the project's own repository. They are listed in a separate section and are never mixed into the price ranking.

Freshness

A page stops being published when its vendor page was last read more than 30 days ago. We re-check every page on the 1st and 15th of each month. If a re-check finds that a quoted price has changed, the tool is taken down until its figures are read again and its note is reviewed again.

Cost per monitor and currency

Cost per monitor is the entry plan's monthly price divided by the monitors it includes. It is shown only for per-plan or per-monitor pricing. Prices in other currencies are converted to US dollars at European Central Bank reference rates (currently 2026-11-06); the original price is always shown on the tool's page.

Notes, and who reviews them

Each tool page has a short editorial note. A draft is written from the verified figures only, and a person reviews it before it is published: the check rejects a note that uses a number not found in the facts. If a tool's facts change after a note was approved, the page is taken down until a person approves it again.

The "best" and comparison pages

The best tools page and the "X vs Y" pages are generated from the same checked figures. Each pick states its rule, such as "most free monitors", and shows the figure and the date it was checked. Ties are shown as ties.

What we do not do

• No vendor pays to change a figure, a pick or an order. Paid placement does not affect facts.
• We use no star ratings or user reviews, because we have none.
• If a link ever earns us a commission, it will be labelled as such. There are none today.
• We are not affiliated with any vendor listed.

Spotted a mistake?

Each tool page links its source, so you can check it yourself. Send a correction. We fix what we get wrong.