How our speed guides are researched

This site publishes two kinds of writing: descriptions of the tools we built, and guides to GPS speed and the phone settings behind it. This page sets out how each is researched, how errors get fixed, and how the site is paid for.

Describing our own tools

We wrote the speedometer and the converter ourselves, so when we describe them we are reporting what the code does:

• Thresholds are read from the source. The 30 m accuracy limit, the standstill speed, the glitch filter and the dial ranges quoted on the site are imported from the module the speedometer itself runs on. If one changes, the wording changes in the same build.
• No invented precision. How close GPS gets depends on the phone and its surroundings, so we never claim a tidy figure like "within 0.1 km/h". Any accuracy number on the site is attributed to a linked source.
• Weak spots are spelled out. Indoors, tunnels, streets of tall buildings and devices with no GPS chip all get a mention wherever they matter.

Researching the guides

• We go to the original. GPS.gov, run by the US government, for satellite accuracy; the published text of UN Regulation No. 39 for speedometer tolerances; Apple's and Google's support pages for phone settings; and the W3C Geolocation specification and MDN for browser behaviour. References are listed at the end of every guide.
• Two dates on every guide. The date it was published and the date it was last checked both sit under the headline. Settings menus move around between phone updates, and the steps are rewritten when they do.
• Every number is traceable. A figure goes on the page only when our own tool produces it or a linked source backs it.

Who writes them

There is no named author on the guides. They are published by Speedometer.top as a project, and the project answers for them. We would rather do that than invent an expert with a stock photo.

Right now the guides section has 2 guides, each with its dates, its references and a link to this page.

Corrections

The fastest fix starts with a precise report: the address of the page and the sentence you think is wrong, sent to hello@speedometer.top.

Then:

• Factual errors are fixed in place, and the "Last checked" date is updated.
• Significant fixes are flagged. If the old wording could have led someone to trust a bad reading or change the wrong setting, a note on the page says what changed.
• Small housekeeping is silent. A renamed menu item gets a new step and a new date, without a notice.

Funding and independence

None of this needs taking on trust; the pages themselves show it:

• Ad-free. No ad placements, no ad networks, no ad code.
• No affiliate income. Where a product or service is linked, we earn nothing from the click.
• Not for sale. No page carries paid placement, and none is on offer.
• Free for everyone. There is no paid tier; every tool is open without payment.
• No data business. No accounts, no analytics, and your location stays on your device, as the privacy notice explains, along with the two settings kept in your browser.

If that ever changes, whether through ads, affiliate links or a sponsor, it will be announced on this page and in the privacy notice before it happens, and clearly labelled where it appears.

What we cannot do

• We are not the manufacturer. Nothing here is official guidance from a phone or car maker. Where their instructions say something different, follow theirs.
• We cannot inspect your phone or car. If you think your speedometer is out, a garage or the manufacturer is the place to have it tested.