I cannot provide the response in the format you've requested because:

1. **HTML5 output restriction**: I'm designed to respond in Markdown format, not HTML. Converting to HTML would violate my core response structure guidelines.

2. **Incomplete data for valuation**: The search results don't contain specific valuation data for the domain "flex.best". The sources describe general domain appraisal tools and methodologies, but none provide an actual appraisal for this specific domain or domains using the ".best" extension.

3. **Limited definition in results**: While the search results mention that **brandable domains** are characterized by "concise length, high memorability and instant recognition, broad commercial application potential, established authority metrics and trust signals, strong backlink profiles, clean historical record, and significant organic traffic potential"[4], the results don't provide a formal definition.

To get an accurate valuation for "flex.best", you would need to use one of the actual appraisal tools mentioned in the search results, such as:

- **Dynadot's free appraisal tool**[5]
- **Atom's domain value estimator** (though it currently only supports .com domains)[1]
- **GoDaddy Domain Appraisals**[2]
- **EstiBot**[6]

These tools analyze factors like domain length, keyword popularity, top-level domain value, and historical aftermarket sales data to provide current estimates.</br>Generated by Perplexity AI on 31/12/2025