The Fixity Survey Working Group is pleased to announce the publication of the 2025 Fixity Survey Report. As the third iteration of this survey (2017, 2021, 2025), this report continues the longitudinal study of fixity practices. The survey report and accompanying files can be found in OSF or on the Fixity Working Group webpage.

A total of 89 completed survey responses were used in the analysis of the data with 94% of respondents confirming that they use fixity information within their organizations. Checksums were the most common type of fixity information captured, often in conjunction with other methods. Practices vary widely in terms of when fixity information is captured or verified, the frequency of checks, where fixity information is recorded, and what checksum algorithms are used.

The working group was interested in understanding what causes fixity errors, when they happen, and what participants are doing to address them. While it was found that fixity errors were not very frequent, it was interesting to learn more about when and where these errors were occurring. The most common errors were corrupted bit streams or interrupted network transfers. It should be noted that a quarter of the respondents never encountered fixity errors. Actions taken to address fixity errors included checking to confirm if the result was in fact an error, troubleshooting the error, and replacing the incorrect file with a known good copy.

The Fixity Survey Working Group also conducted follow-up interviews with three organizations of different types and sizes to explore fixity practices in more detail. The resulting case studies, included within this report, provide a rich illustration of how fixity is used within specific organizations.

As digital collections continue to grow in scale and complexity, maintaining and improving fixity practices will remain essential to ensuring long-term trustworthiness and accessibility. The results of the 2025 Fixity Survey reaffirm the value of community-wide data gathering and knowledge sharing. They also underscore an important truth: good fixity practice is not a single standard, but a continuum of strategies grounded in institutional context, professional judgment, and a collective commitment to preserving digital heritage for the long term.