Update Rows in Excel in Power Automate

PDF4me Excel - Update Rows is a Power Automate action that modifies existing cells in a workbook in place, matching JSON property names to column headers. Use it to sync database changes, refresh CRM records, or update status columns in an Excel report without inserting or deleting any rows.

What this action does

PDF4me Excel - Update Rows writes a JSON array of objects into existing rows starting at Start Row, matching each property name to a column header. Convert Numeric And Date, Date Format, Numeric Format, and Culture Name control how the values are typed and formatted. It never inserts or deletes rows, only the matched cells change.

How Do I Authenticate My Power Automate Flow?

Every PDF4me action in Power Automate requires a valid connection. Create or select one that holds your PDF4me API key so the flow can authenticate Excel row-update requests securely.

Get your API Key

Important Facts You Should Not Miss

This updates rows, it does not insert them

Objects in JSON Update Data are applied sequentially to existing rows starting at Start Row. There is no key-based lookup, use Add Rows first if the row does not already exist.

The data field is labeled JSON Update Data

It must always be a JSON array, even for a single row. A bare object without array brackets returns a JsonData must be an array error.

Type conversion needs the toggle on

Date Format, Numeric Format, and Culture Name only take effect when Convert Numeric And Date is enabled. Left off, every value is written as plain text.

Power Automate PDF4me Excel - Update Rows action configured with File Content, File Name, Worksheet Name Sheet1, JSON Update Data, Start Row 20, Start Column 1, and Advanced parameters showing Convert Numeric And Date Yes, Date Format yyyy-MM-dd, and Numeric Format N2 — Map File Content and File Name, set JSON Update Data and Start Row, then expand Advanced parameters for type conversion and formatting.

Parameters

Required: File Content, File Name, and JSON Update Data must always be provided. JSON Update Data must be a JSON array, a bare object is rejected.

Parameter	Required	What it does	Example
File Content	Required	Base64 content of the source Excel workbook, mapped from SharePoint, OneDrive, or another prior action.	`[File Content from Get File]`
File Name	Required	Excel filename including extension (.xlsx or .xls), used for processing and output identification.	`data.xlsx`
JSON Update Data	Required	JSON array of objects to update. Each object updates one row sequentially starting at Start Row. Must be an array, a bare single object is rejected.	`[{"Name":"John","Age":31}]`
Worksheet Name	Optional	Name of the worksheet to update. Defaults to the first worksheet if left blank.	`Sheet1`
Start Row	Optional	1-based row number to start updating. Default 1, typically set to 2 or higher to skip a header row.	`2`
Start Column	Optional	1-based column offset for header matching. Default 1 (column A).	`1`
Convert Numeric And Date	Optional	Enables automatic conversion of JSON numbers to Excel numeric values and date-like strings to Excel dates. Default true.	`true`
Date Format	Optional	Excel date format applied when Convert Numeric And Date is enabled. Default yyyy-MM-dd.	`MM/dd/yyyy`
Numeric Format	Optional	Excel numeric format applied when Convert Numeric And Date is enabled. Default N2.	`#,##0.00`
Ignore Null Values	Optional	Skips updating a cell for any JSON property that is null when enabled. Default false, which writes nulls as empty cells.	`false`
Ignore Attribute Titles	Optional	Makes JSON property name matching case-insensitive against column headers when enabled. Default false.	`true`
Culture Name	Optional	Culture code used to parse incoming date and number strings before conversion. Default empty (system default).	`en-US`

Output Fields

Field	Type	What it contains
`document`	Base64	The Excel workbook with the matched rows updated.
`Success`	Boolean	true if the update completed, false if the action failed.
`ErrorMessage`	String	Error description, null when Success is true.
`Errors`	Array	Detailed error objects with Code and Message, empty when Success is true.

What Do the Common Error Messages Mean?

Error Message	Cause	Solution
Request is empty	The request object is null.	Provide a valid request object.
Document is empty	File Content is null or empty.	Map a valid Excel document into File Content.
Invalid worksheet selection	The named worksheet does not exist.	Use an existing worksheet name or leave it blank for the first sheet.
No headers found in worksheet	The target row (or Start Row minus one) has no headers.	Ensure the header row exists directly above the rows you are updating.
JsonData must be an array	A bare single object was provided instead of an array.	Wrap the object in array brackets, for example [{"Name":"John"}].

How Do I Set Up Update Rows in Power Automate?

Add PDF4me → Excel - Update Rows to your Power Automate flow.
Map File Content and File Name from a previous action (SharePoint, OneDrive, or a database connector).
Set JSON Update Data to a JSON array of objects, one per row to update.
Set Start Row to the first row to update (skip header rows) and Start Column for the header offset.
Expand Advanced parameters to enable Convert Numeric And Date and set formatting. Run the flow, the updated workbook returns as document.

Typical Setups

Workflow ExamplesCommon Power Automate flow patterns using Update Rows.

Daily inventory sync

A scheduled trigger queries the database for updated stock levels.
The results are converted into a JSON array matching the inventory sheet's column headers.
Get file content retrieves the master inventory workbook from SharePoint.
Update Rows applies the array starting at Start Row 2, with Convert Numeric And Date enabled for whole-number stock counts.
The updated inventory workbook is saved back to SharePoint.

Order status refresh

A flow triggers when an order status changes in the order management system.
The scenario builds a JSON array with the updated status field for the affected rows.
Get file content retrieves the order tracking log.
Update Rows applies the change with Ignore Null Values enabled, so other order columns stay untouched.
The updated log is saved back to SharePoint.

CRM contact refresh

A weekly trigger queries Dynamics 365 for contacts modified in the last 7 days.
The records are converted into a JSON array with contact and last-modified fields.
Update Rows applies the changes with Ignore Attribute Titles enabled for case-insensitive header matching.
The refreshed contact list is archived with a timestamp.

Practical Tips

This is not a lookup-and-match update

Rows are updated sequentially from Start Row, there is no key column matching. Sort or filter your JSON array to match the row order in the workbook before calling this action.

JSON Update Data must be an array, always

Even a single-row update needs array brackets: [{"Name":"John"}], not {"Name":"John"}. Omitting the brackets returns a JsonData must be an array error.

Start Row usually skips the header

Row 1 typically holds column headers, so most flows set Start Row to 2 or higher to begin updating actual data rows.

Culture Name affects parsing, not just display

Set Culture Name to match how your source data formats dates and decimals (for example de-DE for comma decimals), otherwise conversion can misread values.

Ignore Attribute Titles solves case-mismatch headaches

If your JSON property names differ in case from the Excel column headers, enable Ignore Attribute Titles instead of renaming every header or every JSON key.

Cheat Sheet

Field	Value
Action	`Excel - Update Rows`
Required fields	`File Content, File Name, JSON Update Data (array)`
Default start row	`1 (set to 2+ to skip headers)`
Default start column	`1 (column A)`
Type conversion toggle	`Convert Numeric And Date = true (default)`
Default date/numeric format	`yyyy-MM-dd / N2`
Output	`document (Base64 workbook) + Success + ErrorMessage + Errors`

Common Questions

How do I update existing Excel rows in Power Automate?+

Add the PDF4me Excel - Update Rows action, map File Content and File Name from a prior action, set JSON Update Data to a JSON array of objects (one per row), and set Start Row to the first data row to update.

Does Update Rows insert new rows if a match is not found?+

No. Update Rows only modifies existing cells starting at Start Row, it does not insert or delete rows. Objects are applied sequentially to consecutive rows beginning at Start Row, there is no lookup-and-match against a key column.

Why must JSON Update Data be an array even for one row?+

The action always expects a JSON array of objects. A bare single object such as {"Name":"John"} returns a JsonData must be an array error, wrap it as [{"Name":"John"}] even when updating only one row.

How does automatic type conversion work?+

With Convert Numeric And Date enabled, JSON numbers become Excel numeric values formatted with Numeric Format, and date-like strings become Excel DateTime values formatted with Date Format. Culture Name controls how the incoming values are parsed before conversion. See <a href="https://learn.microsoft.com/en-us/dotnet/standard/base-types/standard-numeric-format-strings" target="_blank" rel="noopener noreferrer">Microsoft's numeric format string reference</a> for the supported format codes.

What happens to a JSON property that has no matching column header?+

It is ignored for that row. Only JSON properties whose names match an existing column header (case-sensitive unless Ignore Attribute Titles is enabled) are written to a cell. See the <a href="https://learn.microsoft.com/en-us/connectors/pdf4meconnect/" target="_blank" rel="noopener noreferrer">PDF4me Power Automate connector reference</a> for the full action schema.

Industry Use Cases & Applications

Lead Status Updates: Update lead qualification status in Excel tracking sheets
Campaign Metrics: Refresh campaign performance metrics from analytics platforms
Customer Records: Sync customer contact information from CRM to Excel
Sales Quotas: Update monthly sales targets and actuals in Excel dashboards