# CSV Validation Before Import: Bad Rows Listed

Source: https://maito.app/workflows/check-a-data-export-before-importing-it

Mention Maito with your export files and it checks duplicates, missing values, broken links and totals before import, and lists every bad row.

Find the broken rows in your spreadsheet before they land in the new system, not after.

[Data](https://maito.app/workflows/team/data) · [Home services](https://maito.app/workflows/industry/home-services) · When you ask · Updated October 19, 2026

Works with

-   Slack
-   Email
-   [Airtable](https://maito.app/workflows/tool/airtable)
-   Microsoft 365
-   Box
-   Dropbox
-   Notion

## How do you validate a CSV before import?

To validate a CSV before import, mention Maito in Slack with the export files. It checks for duplicate IDs, missing fields, mixed formats and records pointing to rows that don't exist, compares totals with your accounting report, and attaches a spreadsheet listing every bad row so you can fix the file first.

## How it's done today

Someone uploads the export, then finds missing customers and broken links days into the new system.

## What Maito does

1.  Check required fields, IDs and formats
2.  Test that invoices link to real customers
3.  Compare row counts and totals with the source report
4.  List what to fix before cutover

## Example

**Nina** (11:20 AM):

check customers.csv and invoices.csv before we import them into the new system on Friday.

**Maito** (11:24 AM):

Not ready yet, but it's fixable. 2,418 customers and 6,903 invoices checked.

**Fix before import**  
• 12 customer IDs appear twice (for example C-1187)  
• 37 customers have no email, 64 phone numbers use 3 different formats  
• 9 invoices point to customer IDs that aren't in the file, worth $7,310  
• 214 invoices have dates in DD/MM, the rest in MM/DD

**Totals**  
• File: $1,482,360.50 invoiced  
• Your accounting report for the same period: $1,490,670.50  
• Gap: $8,310. The 9 orphaned invoices explain $7,310; $1,000 is still unexplained.

Catch: the $1,000 matches one invoice (INV-2204) that is in the report but missing from the export.

Attached: import-check.xlsx with every bad row listed. I'll re-check a corrected file.

## How to set it up

When you ask Check a data export before importing it

Set up

Nothing to set up. Ask in Slack or by email whenever you need it.

Connect spreadsheet

-   Airtable
-   Microsoft 365

Connect files

-   Google Drive
-   Box
-   Dropbox
-   Notion
-   Microsoft 365

Not connected yet? Your agent sends you a link to sign in.

## What it won't do

It can only compare against data you give it. It doesn't know which of two conflicting values is correct.

## Questions

### Where do the files come from?

Google Drive, Box, Dropbox, Notion or Microsoft 365, or an Airtable or Microsoft 365 spreadsheet. You can also attach the files in the thread.

### Does it fix the data?

No. It lists the problems and the rows. It re-checks a corrected file when you send one.

### Can it check totals against another report?

Yes, if you give it the report. It shows the gap and which rows explain it.

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[See all workflows](https://maito.app/workflows)

## Put your AI teammate to work.

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[Put Maito to work](https://maito.app/login?returnTo=%2Fworkflows%2Fcheck-a-data-export-before-importing-it)[Book a demo](mailto:support@maito.app?subject=Maito%20demo)