JPL has a nice data base
Here's a screen shot:
Notice some of the options. You can sort by minimum possible distance. For time range you can choose All available.
They measure their distances in LD (Lunar Distance) or AU (Astronomical Unit). To get kilometers, multiply their LD number by 384,400 or their AU number by 150,000,000.
They also give Vinf. This rock's relative velocity to earth at close approach is of interest.
In many cases asteroid albedo is unknown. So the H (absolute magnitude) doesn't tell us the asteroid's size. Here is a JPL chart telling us the size range an H number might indicate.
This is one of the reasons I yearn for a WISE 2.0 parked at the SEL2 (Sun Earth L2). From SEL2's point of view, the sun, earth and moon all occupy the same small region of the sky. So a small shade suffices to block heat from 3 major heat sources. That gives most of the 3 K sky the infra red scope can radiate heat into.
When we do a visual and infra red observation at the same time, that tells how much light is being absorbed and how much reflected. When we have a handle on the rock's albedo, then H gives us a better idea of the size.