Home Site map Who? How? Why? Press/Info
Trust ICRA? Complaints Contact Webmasters Parents Kids FAQ Label your site ICRAfilter Label generator Label tester Image watermarks Members Associates Become a member Affiliates Case studies Hotlines Links



This filter has been developed to demonstrate a transparent, freely available tool to enable parents to control access to material they deem inappropriate or potentially harmful to their children and at the same time protect freedom of expression. It is designed primarily to demonstrate filtering based on PICS and other techniques and is not, in itself, a complete consumer product. In order to be most useful as a filtering tool, one or more templates will need to be installed (see below).

The filter is based on the idea that self labelling is the most democratic and transparent way of dealing with vast amounts of content and that self-labelling is the primary technology for achieving the balance of several interests. Although it can be combined with other blocking technologies, such as block lists, the product is dedicated to the idea that such blocking is based on trust established between the content provider and the parent, and the list supplier and the parent. Therefore all blocking is transparent so the parent can see why or by whom something is blocked. The parent remains in complete control of what is blocked and what is allowed.

No filter, including this one, can replace parental care while your children are online. Filters are part of the answer, not the whole answer to the problem of your children coming across material you consider potentially offensive or harmful. Many organizations offer advice on what steps you can take to help to protect children and it is recommended you seek such advice.

Return to top

Key features

The filter offers the following functions:

  1. Reading of ICRA labels;
  2. User's own block and allow lists (you can enter sites or groups of sites you always want to block and those you always want to allow);
  3. Templates - sets of rules for what to block or allow based on ICRA labels (or their absence), block lists and allow lists. These are made available by a range of organizations in whose ideas and policies parents can choose to put their trust;
  4. Blocking of various online services including chat and e-mail;
  5. Multiple profiles - you can set different rules for different members of your family.

Return to top


The filter has been designed to give you the maximum possible control over which sites will be blocked and which sites will be allowed. A direct consequence of this flexibility and the very fine control available is that there are a lot of choices to make. Filtering templates provide a quick and easy shortcut. By installing one or more templates, you're letting the template creator(s) set up the filter for you.

A template contains any combination of:

  • Lists of websites which will be blocked (known as "block lists");
  • Lists of websites which will be allowed (known as "allow lists");
  • Rules to block or allow access to websites based on ICRA labels;

For a list of all templates currently available and known to ICRA, please click here.

NB. However many templates you install, your own settings take priority. For example, if you include a site in your own block list it will be blocked no matter what the templates say.

If your organization is interested in creating a template, please click here.

Return to top

Download and installation

The filter can run on all versions of Windows from Windows 95 onwards. Other platforms are not supported. Installation is straightforward but varies slightly depending which version of Windows you are using. Please check the list below and make sure you are ready to install.

  • Windows 95. Before installing ICRAfilter you need to upgrade a file called "winsock" on your computer. This is a free download from Microsoft and self-installs.

    Click here for the updated file and follow Microsoft's on screen instructions. The next item applies to you too.


  • Windows 95, Windows 98, Windows ME (Millennium Edition). You will be asked to enter a supervisor password. This password is required to change any settings on the filter or to uninstall it. In addition, you will be asked to enter a question and its answer. The question will be visible to your children should they try to uninstall the filter so make sure that the answer and the supervisor password are kept secret.

    The question and answer are there to help you should you forget your supervisor password. If you do forget it, and the answer to your own question, you will need to write to your nearest ICRA office (in the UK or the USA) enclosing payment for assistance with removing the filter. Installing the filter signals your acceptance of these terms. Keep your supervisor password safe.

    Your supervisor password can be the same as your override password (see "All users" below) but it is recommended that you use a different one.


  • Windows NT/2000/XP. ICRAfilter relies entirely on the security systems that form part of your computer's operating system. Your computer should be set up so that you, the parent, log on with Administrator rights and your children log on with limited access. You must be logged on to an account with administrator rights in order to install the filter. A user group called "ICRA Admins" is created on installation. Members of this group can change the filter's settings without entering any further password. Users with limited access - i.e. you children - will not be able to access the settings.

    Once set up, this is a very secure method of working but it does rely on your computer being set up in this way. If you are unsure about this, please see the Windows help file which gives detailed and clear explanations.

All users
During the installation process, you will be asked to enter an override password. This is the password you'll enter when you want to allow access to a site the filter has blocked. Since you are likely to type this in front of your children, it is recommended that this password be changed frequently. See the ICRAfilter help file for details.

The filter includes a full help file which, it is hoped, will answer all your questions. This is available for download in various formats as a separate document. This is easier to print and read at your leisure, or perhaps to review before deciding whether to install the filter.

It is strongly recommended that you uninstall any other filtering software you may have before using ICRAfilter.


Get Acrobat Reader

  •   ICRAfilter version 1.0.9 English
      Download now (898 Kb)

  •   Help file PDF format (zipped), formatted for A4 paper.
      Download now (2 Mb)

  •   Help file PDF format (zipped), formatted for US Letter size paper.
      Download now (2 Mb)

  •   Windows Help file format (mainly for use on-screen). English
      Download now (216 Kb )

After completing download and installation, please consider installing one of the templates which various organizations have created. ICRA is working hard to extend the number of available templates in terms of absolute numbers, the range of cultural values expressed and the languages covered. Click here for the latest list.

ICRAfilter is a freeware product. It is offered for free to internet users world-wide to demonstrate how web sites and other internet services can be filtered using ICRA labels and third party templates. Like all software products, there is a potential for conflicts, problems or bugs to arise. No software publisher that we know of, including the largest, offers a 100% guarantee. Although we are confident that ICRAfilter is a practical and reliable tool, problems with its use may arise and must be used at your own risk.

Of the over 30,000 filters that have been downloaded to date, we have had very few complaints or problems. However, there is a known bug which is a conflict under some circumstances and in some environments, with other software programs. This problem, stemming from the filter's interaction with the WinSock2 module in Microsoft Windows has been worked on and a fix is included in the latest release of ICRAfilter, Version 1.0.9. We would appreciate reports on other bugs or problems, and, should they arise, please see our Frequently Asked Questions. If you still don't find the answer you're looking for, feel free to e-mail us with full details of the issue at: .


The filter has been designed to fail safe. If individual files relating to the filter are tampered with, the most likely outcome is that all online activity will be blocked. Furthermore, if files are deleted without using the proper uninstall option, it is possible you will need to seek advice from your computer supplier. This could lead to you having to completely reinstall all software and losing all your data in the process.

As set out in the terms and conditions displayed when installing this software, The Internet Content Rating Association accepts no liability whatsoever for data lost through tampering with the filter.

Return to top

Notes for software developers

Internet Designers .net
ICRAfilter was developed by Internet Designers Ltd. and financed with the assistance of ICRA members AOL Europe, British Telecom, Internet Watch Foundation and PAGi.

The filter has a modular architecture. The service is quite separate from the user interface for instance. Native security features of NT/2K/XP are exploited to provide secure storage of relevant files. A key module is the PICS engine. This is the module which interprets labels and PICSRules Files. These files form the basis of the whole filter and are defined formally by the World Wide Web Consortium at http://www.w3.org/TR/REC-PICSRules. As well as standard URLs, PICSRules Files (PRFs) can support hashed URIs, as defined by Clive D. W. Feather, one of the authors of the original PRF specification and a member of ICRA's board.

Finally, ICRA has defined an optional extension to PRFs to include icons. Click here for the formal definition.

As stated elsewhere, ICRA is not a software company. ICRAfilter is designed to prove the concept - to show how self-labelling and self-regulation really is the way to protect children from potentially harmful content whilst preserving freedom of expression on the internet. Modules from the filter can be licensed from ICRA in whole or in part and it is very possible that we will shortly be making the filter available as an open resource.

Whatever other filtering technologies are employed by your product - text or image analysis, list-based filtering or other methods - the addition of support for reading ICRA labels and importation of templates from a full range of organizations can only add value to it. That's why the filter's source code is freely available.

ICRAfilter is an Open Source project managed through Source Forge. The code comes with an "Apache-stye" licence allowing contributions to be made and for commercial exploitation of the code if desired.

  • To see the licence for the filter and its components, please click here.
  • To go to the Source Forge project, please click here.

Powered by CI Host ICRA