Parents will receive an e-mail every time police issue an appeal about a missing paedophile, under a scheme which is being launched.
Parents can already see a list of wanted paedophiles on Ceop's website
The Child Exploitation and Online Protection (Ceop) centre will send out a warning about any new face added to its "Most Wanted" list.
The site has received more than 12 million hits from 130 countries since going live five months ago.
The public can register for the e-mail updates at www.ceop.gov.uk/wanted.
Since November, public reports have led police to six child sex offenders who had gone on the run after failing to comply with their parole requirements.
Ceop chief executive Jim Gamble said the email alerts would allow the details of wanted offenders to be circulated much more widely.
"As visitors to the site increase, so too does the possibility that an offender will be recognised and reported," he said.
"Whether you're involved in child protection or law enforcement, or you're simply an interested parent or a concerned member of the community, everyone has a role to play when it comes to locating convicted child sex offenders who are missing."
The website shows the names, ages and photographs of wanted offenders and their last known whereabouts, but not the details of their convictions.
It is run in conjunction with the Crimestoppers Most Wanted site, which aims track down Britain's most dangerous missing criminals.
Mr Gamble added: "To any offender out there who thinks they can escape their registration requirements, I'd say, 'Think again'.
"From now on, the chances of you remaining hidden will rapidly diminish with every person that registers for updates."