Age Check Certification Scheme evaluation for Yoti Facial Age Estimation

profile picture Matt Prendergast 3 min read
Woman surrounded by green plants using her smartphone

We are pleased to announce Yoti has been re-evaluated by the Age Check Certification Scheme (ACCS) for our facial age estimation (FAE) on our latest September 2024 model.

ACCS now report our Mean Absolute Error (MAE) for 18 year olds is just 1.05 years, with a Standard Deviation (SD) of just 1.01 years. ACCS first tested Yoti’s September  2020 model in November 2020, reporting the MAE for 18 year olds to be 1.79, demonstrating our continued effort to improve the performance of our model.  

Yoti has been training its FAE model since early 2018 by using data captured mainly on mobile phones. From our experience, the vast majority of demand for digital age checks comes from end users choosing to use their phone to capture their selfie.

Yoti’s latest self measured MAE for 18 year olds, using a diverse test set of 9,091 18 year olds published in our September 2024 white paper, is 1.24 years.

NIST’s recent evaluation of Yoti’s September 2024 model reports that for 18 year olds;

  • An MAE of 2.63 years using Visa images captured in Mexico consular offices &; 
  • An MAE of 2.90 years using Application images captured in US immigration offices.

It is hugely beneficial to the industry that NIST now independently evaluates eleven vendor FAE models including Yoti. But it is important to understand the NIST test images are not captured on mobile phones and the latest ACCS independent testing shows this makes a big difference to accuracy.

  • ACCS independent testing reports 99.3% of 18 years are reliably estimated to be under 25 – a 7 year buffer. 
  • ACCS also report that 97.8% of 18 year olds are reliably estimated to be under 21 – a 3 year buffer.
  • 94.2% of 18 year olds are reliably estimated to be under 20 – a 2 year buffer.

This means a very high percentage of adults can take a selfie and use Yoti FAE to show they are 18 or over. Some may claim it is not accurate, easy to spoof or that biometrics is biased against females or skin tone. We publish results by gender & skin tone which demonstrate there is no material bias.

Many regulators are recognising FAE is a privacy preserving, proportionate and effective solution for age assurance. Some regulators may think six year old safety tech as immature, and can’t yet be relied upon for online age checking. Some don’t yet feel comfortable accepting any companies ‘marking their own homework’. Hopefully ACCS measuring our MAE slightly lower than we measure it to be, will help to build trust.