ICANN invites public feedback on string similarity data ahead of next gTLD round
Stakeholders are invited to review the proposed code points and degrees of similarity or suggest additions. Feedback is open until 4 December 2025, after which ICANN will finalize the data for use in the next gTLD evaluation process.
The Internet Corporation for Assigned Names and Numbers (ICANN) has published draft String Similarity Evaluation (SSE) data and is seeking public comments. The feedback period runs from October 16 to December 4, 2025. This data will guide how new domain names are reviewed in ICANN’s upcoming New gTLD Program: Next Round.
What is string similarity evaluation?
When organisations apply for new generic top-level domains (gTLDs) – for example, domains beyond .com or .org – ICANN needs to ensure that proposed domain names are not too visually similar to existing ones. This is to prevent confusion among users. The String Similarity Evaluation is a process that compares proposed names (and their variant forms) against existing domain names, reserved names, and variant names. If two names are deemed ‘similar’ under agreed criteria, neither might be allowed to proceed.
To aid this process, ICANN and script experts have prepared similarity data across scripts (writing systems). The SSE data lists pairs of characters (‘code points’) that may look alike, along with a ‘degree of similarity’ value. Reviewers will use this as part of a pre-screening step before a manual evaluation.
What’s being asked of the public
ICANN is asking stakeholders to review the proposed similarity data and give feedback in two main areas:
- Whether the proposed code points (characters) marked as ‘similar’ are appropriate
- Whether the assigned degree of similarity is correct
- Suggestions for additional code points that should be included in the list
Contributors are expected to examine ICANN’s methodology and analysis reports before commenting, since these documents explain how the data was compiled and how to interpret the results.
Why this matters
The next round of gTLD applications is expected to open in April 2026. Using accurate similarity data helps ensure fair and stable operation of the Domain Name System (DNS). By catching ambiguous or confusing domain name proposals early, ICANN can protect users from mistakes, phishing attacks, or misuse that exploits visual similarity.
Because the number of possible comparisons is large, especially when multiple scripts and variant names are involved, having a reliable pre-screening tool reduces manual workload and helps the independent String Similarity Evaluation Panel focus efforts more effectively.
Next steps
After the public comment period closes on 4 December, ICANN will review and incorporate feedback and finalise the SSE data. Then it will integrate that data into its SSE Tool, which supports the manual review by the SSE Panel.
Questions or input should be submitted through ICANN’s Public Comment platform or via the contacts provided in the announcement.
