The results of childminder inspections in England are to be published on the internet from next year.
Currently, parents have to contact childminders themselves
Reports are currently only available if providers are contacted directly, making it difficult for parents to compare quality.
Ofsted, the education watchdog, said postcode searches would allow a more informed choice.
The service is due to go online from April 2005, the start date for the next childcare inspection programme.
'Get in touch'
To ensure confidentiality and child security, the childminder's name and address will not be published on the internet.
Instead, reports will list only part of the postcode and the registration number.
When a parent finds a suitable provider, they will have to contact the Children's Information Service.
An Ofsted spokesman said: "It will be up to the childminder how much information they want the service to give.
"If they are fully booked, they might not want to give their name, address and telephone number.
"However, most should be happy for parents to have details and to get in touch."
This confidentiality arrangement follows consultations with 70,000 parents and childminders.
Ofsted's chief inspector, David Bell, said: "I hope it will enable parents to make informed choices about the care their child receives."
He added: "By publishing the childminder's registration number and part of their postcode, we will strike a balance between protecting children, enabling parents to locate childcare in their area and reassuring childminders."
Ofsted took over the responsibility for the registration and inspection of day care and childminding in September 2001.
There are 99,300 registered childcare providers in England. Of these, 68,200 are childminders and 31,100 were daycare providers.