My company has recently posted internal salary ranges for job titles. There's the bottom of the range, a 33% mark, and the top of the range.
Everyone gets paid at least the bottom of the range. After proving competent they must be on the 33% mark. Some are paid above the top of the range but it's rare.
A given job family has different titles, broadly Junior-'Vanilla'-Senior-Principal. A junior might be on 25-45, vanilla on 35-55, a senior on 40-65, a principal on 55-80, or whatever (triple those for US wags I guess). That fits the "more experienced" part. You could advertise for a principal and find someone who just about scrapes in, so pay them 55, find someone great and offer them 80.
When advertising externally though, this information is not available - unless you know someone who already works there, which is crazy.