How these cards are made

What a card is based on

Most cards are compiled from the vendor’s documentation, pricing page and terms, and that is all such a card claims to be.

A card can also be marked Tested hands-on, which means we held an account or an API key and used the tool: pulled data, ran into the free-tier limit, checked the documentation against what it actually did. That badge comes with a note on the card saying what was done. None of the 60 cards carries it yet.

The same fields on every card

Every card fills in the same blocks whatever its category: what it costs, what the free tier allows, what it covers, how you connect to it. That is what makes the listings filterable. A field we have not checked is left blank rather than filled with a guess.

Blank, and “None”, are different answers

A field we have not checked is left empty and renders as an em dash. A field that does not exist — a library that charges no trading fee, a venue with no maker rebate — is recorded explicitly and renders as None. The two look alike and mean opposite things, so the build treats them separately: a card that could not price a fee leaves it empty and the validator records the gap, rather than publishing “None” and claiming nothing is charged.

Fees are converted before they are compared

Venues publish trading fees in units that do not line up. Some quote a coefficient applied to the price, some a percentage of what the fill costs, some a flat charge per contract per side. The same printed number can mean two different things, and one venue quoting 3.00% can be cheaper than another quoting 1.75%.

So the fee field on every card carries one thing: the effective taker fee at a price of 50 cents, as a percentage of the dollar a winning contract pays. It is the only figure that can be read across venues. The whole curve, the coefficient and any per-category table live in the card’s own pricing section, where prose can hold what one number cannot — and what a trade actually costs explains the conversion.

Dates are per field

Pricing changes in weeks and availability overnight, so each block carries its own verification date rather than one “last reviewed” date for the whole page. Dates that have gone old are flagged.

Words we do not use

A short vocabulary is rejected by the build rather than discouraged in a style guide: terms that assert conduct by named, living companies, and terms that promise a reader an outcome. They are checked across every page here, not only the ones about venues. Where a claim of that shape is true, it is written narrowly and attributed — a named regulator’s finding on a named date, or a court’s holding with the case and the posture it was decided on.

What this catalogue does not do

It does not publish odds, forecasts, picks or any statement about which contract to take. The boundary is drawn at the mechanism rather than at the topic: a product sold to tell you what to buy is outside the catalogue, and so is a page here that would do the same. That is also why nothing on this site is dated as a post — guides are reference pages corrected in place, carrying the date they were last changed and no publication date, because a dated post reads as stale whether or not it still holds.

Paid placement

Nothing in the catalogue is sponsored today and no card carries an affiliate link: all 60 of them are free listings pointing straight at the vendor. The rules below are the ones a paid placement would run under, written down before there is one to argue about.

A sponsored card is marked Sponsored wherever it appears, and an affiliate link is labelled at the link itself rather than only in a footer. Every sponsorship carries an end date, because an undated sponsorship never ends.

A sponsor may also supply its own copy, which is stored apart from ours and rendered in its own block headed From the vendor. It is never edited into our description, and our description is never written from it.

That label and that block are the whole of it. Money does not buy a position in a listing, inclusion in the catalogue, a rating, or a single extra field on the card — a paid card is filled in against the same blocks as a free one, and a limitation described on it stays described.

Listings sort by name, never by tier. The one ranked list on the site is the picks on an alternatives page, and each of those prints the rule it was ordered by at the top of the list; sponsorship is not part of any of them.

That is how the site is run today, and this page is where a change to it would be written down. The affiliate disclosure covers the links themselves, and advertising covers the terms from a vendor’s side.