CSV data cleaning checklist
Build a repeatable cleaning sequence: profile the file, normalize structure, clean values, validate output, and keep a change record.
These guides are focused on real files people need to clean: spreadsheet exports, CRM lists, order reports, bank transactions, survey responses, and recurring Python pipelines. Each guide ends with a local-first workflow you can test in the browser tool.
Use the checklist, Excel, date/number, and schema guides before importing a file into a spreadsheet or BI tool.
Use the CRM, ecommerce, bank, and survey guides when the CSV comes from a specific workflow with domain-specific risks.
Use the Python automation guide to turn the same cleaning rules into repeatable scripts with reviewable output.
Build a repeatable cleaning sequence: profile the file, normalize structure, clean values, validate output, and keep a change record.
Handle semicolon exports, quoted commas, date conversion, leading zero identifiers, and values Excel tries to reinterpret.
Define expected headers, duplicate-header rules, type checks, required fields, and exception handling before loading data.
Standardize date shapes, numeric separators, null values, and ambiguous locale formats before calculating metrics.
Normalize contact fields, lifecycle stages, owner names, blank values, and duplicate contacts before import or campaign use.
Protect order IDs and SKUs while cleaning totals, status labels, fulfillment dates, and duplicate rows.
Prepare transaction exports for reconciliation with date, amount, reference, and audit-trail checks.
Preserve open-text answers while cleaning respondent IDs, submitted dates, ratings, segment labels, and duplicates.
Move from manual cleanup to repeatable scripts with deterministic transforms, logs, validation, and local QA.
We keep the guide set intentionally narrow. Pages are included here only when they explain a distinct workflow, name concrete failure modes, and connect back to a testable cleaning routine in the local tool.