With Uber gearing up to formally file to go public Thursday, the ride-hailing giant will inevitably be compared to its smaller rival: Lyft, which just went public last month.

But following Lyft's recent bad stock market performance, investors will be scrutinizing Uber's business closely as they get their first look at its numbers and operations through the filing.

Some key financial metrics investors will be watching for once it opens up its books.

First, because Uber is much larger than Lyft with operations that go beyond its ride-hailing business and extend into areas like food delivery- in markets ranging from the U.S. to North Africa, it clocks much higher revenues than Lyft.

But looking at growth, Uber may take a back seat to its smaller rival since Lyft has rapidly been gaining market share - meaning its revenue growth has been outpacing Uber's.

Next is profitability, in this case, both companies will look very similar in one major way.

Both don't make any money.

But Uber is expected to argue that its scale will give it a big advantage in terms of profitability over the long run.

It will likely also point out that its year-over-year-losses are down, while Lyft's ticked up over the same time frame.

Another number investors will be looking at is monthly active users.

Lyft had nearly 17 million monthly active riders in the fourth quarter of 2018.

Uber is likely to have much more than that due to its wider, global presence.