The Scenario
It's the third time this quarter that someone from the marketing ops team has asked you to push company_size data into Mailsoftly contacts. The first two times you did it by hand. Two hundred fifty rows. One contact at a time. Open the record, find the custom field, type the value, save.
This time there are 250 rows again, except now there's also an industry field and a plan_tier field — all in columns B, C, and D, with Mailsoftly contact IDs in column A.
The bad version:
- Open the first contact in Mailsoftly, find the custom fields section, type the company_size value from column B, scroll to find industry, add that value, scroll again for plan_tier.
- Close and open the next contact. Repeat 249 more times.
- Somewhere in the middle, lose track of which row you are on and update the wrong contact.
Your cognitive load shouldn't be measured in browser tabs.
The Easy Way: One Prompt in SheetXAI
SheetXAI is an AI agent that lives inside your Excel workbook. Through its Mailsoftly integration, it can read your contact IDs and custom field columns and push all updates in a single operation — without you opening a single contact record.
Open the workbook with your contact data and run this prompt:
For each row in this worksheet, add the custom field value from column C to the Mailsoftly contact with the ID in column A using the field name from column B, and write the result status into column D
What You Get
- All 250 rows processed sequentially, each contact's custom field updated with the value from the specified column.
- Column D filled with DONE for successful updates and NOT FOUND or ERROR for any rows that failed.
- A full record of what was updated and what wasn't — reviewable without logging into Mailsoftly.
What If the Data Is Not Quite Ready
Multiple custom fields per contact — all in separate columns
The workbook has company_size in column B, industry in column C, and plan_tier in column D. Each needs to be updated on the same contact.
For each row in this worksheet, update the following custom fields on the Mailsoftly contact with the ID in column A: set company_size to the value in column B, industry to column C, and plan_tier to column D. Write 'DONE' into column E if all three succeeded, or list which fields failed.
The field names are in a header row, not hardcoded
The column headers in row 1 are the exact custom field names, and you want to map columns dynamically rather than specifying them manually.
Using the column headers in row 1 as Mailsoftly custom field names, update each contact identified by the ID in column A with the values in the remaining columns. Write update results in the last column.
Some custom field values need formatting before they go in
The company_size values are things like "1-10 employees" but Mailsoftly expects just the number "10". The plan_tier values are inconsistently capitalized.
For each row in this worksheet, extract just the maximum number from the company_size value in column B before updating the Mailsoftly custom field. Normalize plan_tier values in column D to lowercase before updating. Write all results in column E.
Look up contacts by email, update three custom fields, and log everything in one pass
The workbook has email addresses in column A rather than Mailsoftly IDs, and you have three custom fields to update plus a status column to fill.
For each row in this worksheet, find the Mailsoftly contact by email address in column A. If found, update company_size with column B, industry with column C, and plan_tier with column D. Write the Mailsoftly contact ID in column E and the update result in column F. If the contact is not found, write 'NOT FOUND' in column F.
Ask for the lookup, the updates, and the logging in one prompt — it's all one operation.
Try It
Get the 7-day free trial of SheetXAI and open any Excel workbook with Mailsoftly contact IDs and custom field data, then ask it to push all updates in a single prompt. See also: Bulk assign tags to Mailsoftly contacts and the Mailsoftly overview.