is there ubersuggest keyword difficulty measurement and volume is correct ?

hello everyone,

anyone can confirm ubersuggest keyword difficulty is correct?

i find the keyword with different KW difficulty and volume in other sources rather than ubersuggest ..

for example this one keyword in ubersuggest Diff 21 volume 180k
in other source semrush diff 0 volume 50

and if there any way to get keyword difficulty for free