The Law Society is launching an internet service which will allow firms to compare their financial performance with their competitors.
Members of the society's law management section will be able to use the new benchmarking service to measure their profitability against other firms of similar size and area of work, although all the information will be anonymous.
Practices will also be able to see how their performance compares to the most profitable firms in the country.
"As far as I am aware this sort of facility has not previously been available to firms," says Gail Hardcastle, manager of the section.
"Most lawyers told us they were in the dark about how to compare their costs to others."
Performance figures from the Law Society's latest panel survey of 500 firms will provide information including average earnings, staffing costs and overheads.
The information will be available to members on the management section's website at www.lms.lawsociety.org.uk.
Membership of the section is open to anyone with responsibilities for management in legal practices, and costs u125 a year.
Information on how to join is available on the website.
Fox Williams senior partner Ronnie Fox says: "This will be an extremely useful service which will help firms manage themselves more efficiently.
"There are commercial services which do surveys like this, but it is always questionable how representative they are.
"The Law Society has access to a true cross section of firms and I think this will be used by firms of all sizes."
A benchmarking system allowing firms hoping to operate under contracts with the Legal Aid Board to monitor their costs for advice and assistance is also being developed.
It will rely on practices submitting their own data, and currently has information from 15 firms.
The section also plans to launch an online discussion forum.