[hrnnnnnn]

According to this calculator [1] it would take 11.274 times the mass of the earth to create a black hole with a radius of 10cm.

[1] https://www.omnicalculator.com/physics/schwarzschild-radius

[kamaal]

0.0001 km, or 10 cm would take 0.00003385 suns, or 6.72857 × 10²⁵ kg

Obviously that's not possible by today's physics.

But lets say it was possible, by placing it some where space, how would one make it ?

[JsonDemWitOster]

I'm less ambitious and I just want a 1 cm blackhole for display purposes, cool thing to show off to my guests.

Imagine my disappointment at finding out that I'm gonna need about 10^47 chonky house cats to make a 1cm blackhole! Where could I find that!

[hrnnnnnn]

If you make it 0.887cm you get a nice round one-earth-mass :D