A prop firm, in the retail sense the word now usually carries, is a company that sells you a paid evaluation on a simulated trading account and funds a simulated account for you if you pass, paying a published share of the gains. That is the whole product. Everything else is the specific rules each firm attaches to it, and those rules are where the firms actually differ.
The one-paragraph version, expanded slightly
You choose an account size, pay a fee, and trade a simulated account until you either reach a profit target or breach a loss limit. Reaching the target funds you; breaching the limit ends the attempt and you can usually pay a reset to try again. Once funded you keep a published share of gains, subject to payout rules. Nothing about this involves being hired, and no firm in this index gives a trader real capital to trade at any stage.
Not an institutional desk
The institutional version of proprietary trading puts the firm's own capital at risk, employs the trader, negotiates the share privately and charges nothing to be considered. The retail version charges to be evaluated, simulates the account and publishes the share. The name is shared and almost nothing else is. This matters when reading marketing that borrows the prestige of the institutional model for a product with different economics.
What to compare, given they all say the same thing
Every firm advertises a similar headline, and the numbers bear that out: of the eight firms here publishing a profit split, the minimum, median and maximum are all 90%. The differences sit in the loss limit. A trailing drawdown follows your account's high water mark upward, sometimes including open positions; an end-of-day drawdown moves once a day on realised profit. Bulenox publishes both and makes the choice explicit, which is the clearest illustration that these are two products.
Which firms are not here, and why that matters
This index covers ten firms whose own pages can be fetched and quoted. Apex Trader Funding, Elite Trader Funding and TickTickTrader return HTTP 403 to our requests, and Funded Futures Network and Pure Futures do not answer, so none of them has cells here. Apex is among the largest firms in the market. Any comparison you read, including this one, is a comparison of the firms its author could actually read, and it is worth asking which ones are missing.
Other questions people ask
Is a prop firm a broker?
No. A broker gives you access to markets with your own money. A prop firm sells an evaluation and, if you pass, pays you a share of gains on a simulated account it owns.
Do you need experience to join one?
No firm in this index publishes an experience requirement. What they publish are rules, and the rules are what decide the outcome rather than any entry criteria.
How much does it cost?
The two verifiable entry prices in this index are TradeDay from $45 and Uprofit from $29, both on the dates shown and both the bottom of a tiered range.
Can you lose money with a prop firm?
You can lose the fees you pay, and the reset fees if you restart. Because the accounts are simulated, you are not exposed to trading losses beyond what you have paid the firm.