How to convert a customer csv to json for marketing apis
- Step 1Export your contact list as CSV — Export the list from your existing system or audience platform as a CSV with header row.
- Step 2Map the headers to API field names — Use the CSV Header Rename tool first if columns need to match Mailchimp merge fields or HubSpot property names.
- Step 3Convert to JSON — Drop the CSV here. For most batches, 'array of objects' with type inference on is correct.
- Step 4POST to the API — Send the array as the operations body in Mailchimp or HubSpot bulk create requests.
Frequently asked questions
Will my customer data be uploaded?+
No. Conversion runs locally in your browser. The list is never sent to JAD Apps and is only sent to your CRM when you fire the API request yourself.
How do I ensure email is the unique key?+
Most CRMs upsert on email. Run the CSV Deduplicator on the email column before conversion to remove duplicates from the source.
Can I send tags as an array?+
CSV cannot represent arrays directly. Either pre-split a 'tags' column with the Column Value Splitter, or post-edit the JSON to wrap the value in [ ].
Privacy first
Conversion runs locally in your browser. No file is uploaded — only metadata counters are saved for signed-in dashboard stats.