WEB DATA WORKSHOP
How to clean scraped data before using it
Check duplicates, missing fields, freshness and source traceability before a dataset enters another workflow.
A successful extraction can still produce an unusable dataset. A parser may return the wrong text, a page may repeat the same record, or an export may mix old and new formats. Make a copy of the raw data before cleaning so every transformation can be explained.
Check the shape of the table
Count rows and columns. Look for repeated header rows, shifted cells and fields that contain entire page sections. Pick five records spread across the file and compare them with their source pages. If the schema is wrong, fix extraction rather than hiding the error with cleanup.
Separate exact duplicates from similar records
An exact-row duplicate can usually be removed after checking the export's purpose. Two organizations with the same name may still be different businesses. Choose an identifier deliberately: a source record ID or normalized website URL is often more useful than a display name. Keep a review list for uncertain matches.
Normalize carefully
Trim accidental whitespace and standardize explicitly defined categories. Preserve the original field when a transformation loses information. Do not invent missing email addresses, infer country codes without evidence or turn an empty price into zero. Missing and zero mean different things.
Measure what matters
Report the number of raw rows, removed duplicates, missing required fields and final valid records. Record the collection date and any source errors. Those simple numbers tell the next person what was checked and what remains uncertain.
Prepare a controlled handoff
Use the CSV cleaner for exact duplicates and whitespace. Keep sensitive data out of unnecessary files and share only the fields the recipient needs. Collection does not automatically justify outreach; establish the appropriate contact basis and honor opt-outs before starting a communications workflow.
Our Kandrex resource explains questions to ask before handing approved contacts to a calling tool. For recurring extraction, validation and system integration, CustomWebX can be evaluated separately. Neither service replaces the source checks described here.