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Hash List

Child playing with a kite - caption: All children deserve to be protected from sexual exploitation

Stop anyone from uploading, downloading, viewing or hosting images and videos of child sexual abuse with our Hash List.

 
Our Hash List is the best way to protect your customers, colleagues and services from online images and videos of children being sexually abused.

What is the Hash List?

We turn child sexual abuse images and videos into unique codes (hashes) – think of it as a digital fingerprint. We do this using Microsoft PhotoDNA. With our list, you'll be able to automatically match known images and videosbefore they appear on your services. You'll also be able to remove illegal images and videos already on your services. You'll receive an updated list every day.

Why do I need it?

If people can upload, download, view or host images and videos on your services, you probably need our  Hash List.

You'll be able to stop:

  • the upload of a child sexual abuse image or video on your system
  • the sharing of an image or video through your services
  • the use of your hosting services by a child sexual abuse website.

So using our Hash List will:

  • make your network safer
  • protect your customers
  • save your employees time and distress
  • protect the victims from repeat victimisation.

How does it work?

We’ve teamed up with Microsoft to make it easy for companies to use our Hash List, with a cloud-based automated system. It’s impossible for most companies to manually scan every image and video that’s uploaded onto their platforms. The IWF Hash List does this for you in the background – without affecting your users’ experience.

It means you can compare anything from a single image or video to the millions of images and videos uploaded through your platforms daily. The Hash list can flag illegal images and videos already in your systems and prevent new ones being uploaded. 

Corporate Vice President, Microsoft EMEA, Michel Van Der Bel says: “The impact of IWF’s work has been profound. They have made great progress, but there is more to be done. This is a journey. Microsoft was delighted to be able to employ the technology of our cloud based service to support IWF’s Image Hash List. It’s great work and we are very happy to be involved.”

IWF Deputy CEO, Fred Langford says: “The collaboration with Microsoft and our access to the police database makes this development unparalleled globally. For us, this development could revolutionise the way we work and give peace of mind to the thousands of children, whose images have been shared again and again. We currently have more than 200,000 unique hashes on the list but we’re looking at potentially millions.”

Enhanced quality checks

Two of our expert analysts check each child sexual abuse image and video. These enhanced quality checks mean each image and video is categorised accurately before it reaches your systems. International companies trust the IWF Hash List and use it with legal confidence. We add thousands of images every week.

Security

You can download the list via an API, avoiding the need for additional, external hardware - making access to our list even more secure.

International Deployment

Our hashes are categorised for international use. So whether your services focus on a single country or a multi-national platform, we tailor the list to what you need.

Better than traditional hashes

We help you keep up with the criminals. Unlike traditional hashing technology, an image can be resized, cropped or colours changed and our hashes will still find a match to the original image.

How do we find illegal images and videos?

The images and videos on our List come from:

  • public reports
  • our analysts actively searching for them - we're the only hotline doing this
  • the UK Home Office’s Child Abuse Image Database (including images that aren’t yet online).

Who can use it?

IWF Members can use the IWF Hash List under licence. Companies that will benefit include:

  • filtering providers
  • hosting or file sharing services
  • social media and chat services
  • data centres.

Two versions available

We provide both PhotoDNA and MD5 versions of the hashes.

Get in touch

To talk about how our Hash List could help you, email members@iwf.org.uk or call +44 (0)1223 20 30 30.

Microsoft Logo“The impact of IWF’s work has been profound. They have made great progress, but there is more to be done. This is a journey."

"Microsoft was delighted to be able to employ the technology of our cloud based service to support IWF’s Image Hash List. It’s great work and we are very happy to be involved.”

Michel Van Der Bel, Corporate Vice President, Microsoft EMEA

Interested in becoming a Member?

Fill out our membership enquiry form to help us work out what services you will benefit from

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