Start with the simplest rule that is easy to review
If the job only needs a project prefix, standard suffix, fixed text replacement, numbering or zero padding, regex adds unnecessary complexity. Basic rules are easier to audit before download.
FileNest keeps core batch renaming free. Advanced rules should earn their place by removing recurring setup work, not by turning an occasional rename into a paywall.
- Fixed prefix/suffix: basic rules.
- 001, 002, 003: numbering and zero padding.
- Human-defined sequence: custom ordering.
- Repeatable structural pattern: consider regex.
Use regex when filenames share a stable structure
Dates, version tokens, department prefixes and other repeatable structures can be matched with a regular expression. Regex runs the explicit pattern you provide; it does not understand filenames semantically.
Test against representative files first, then review the complete old-name → new-name preview, especially extensions, dates and sequence numbers.
Use an original,new CSV when every file has an approved target
Client lists, SKU sheets, asset registers and approved naming tables fit one-to-one mapping. Current FileNest uses an original,new structure so the source-to-target decision remains auditable.
Prefix, suffix and numbering can still run after mapping. Review duplicate targets, invalid characters and empty names before download.
Save templates and use Pro when the workflow actually repeats
When the same rule returns every week, month or client project, storing an already-reviewed rule reduces repeated setup and human error. Regex, CSV mapping and saved templates are current Pro advanced capabilities.
The 24H Pass is for eligible standard-processing bursts and does not unlock regex, CSV mapping or saved templates, so one-day volume and recurring advanced naming remain separate paid needs.