File Formats
Altera accepts uploads in Matrixify‑formatted files so you can migrate or bulk update store data with zero reformatting. We currently support three container formats
Excel workbooks
Single CSV Files
ZIP Archives of Multiple CSV Files
The file size limit for any upload is 250 MB.
Excel Workbooks ( .xlsx)
One or more worksheets can be included in the same workbook.
Sheet names drive the import - e.g. a sheet named
Productstriggers a product import,Customerstriggers a customer import, and so on.
Single CSV File ( .csv)
Use when importing one data entity at a time.
Here, the file name (before the extension) determines the import type-
products.csv,orders.csv,collections.csv, etc.CSV Delimiters: We recommend using the comma (
,) delimiter for best compatibility. However, we also support other standard delimiters including:Tab (
\t)Semicolon (
;)Space ()
Colon (
:)Pipe (
|)The app will automatically detect which delimiter your CSV file uses.
ZIP Archive of CSV Files ( .zip)
Combine multiple CSVs into one compressed file.
Each CSV inside the ZIP is treated independently; its file name sets the import type.
Changing Data Type Mapping
If your sheet or file names don’t match the object types (products, customers etc..), no worries. After the upload completes, you can manually assign each sheet or CSV to the correct data type before starting the import.
File Size Limit
Format | Maximum size |
| 250 MB per upload |
Need to upload more than 250 MB? Contact us, or split your data into several files or compress multiple CSVs into separate ZIPs, each under the limit.
Field Reference
For a complete list of accepted columns for every type of data, see our field reference.
Row Grouping
When importing data that spans multiple rows (such as products with multiple variants, orders with multiple line items, or collections with multiple products), Altera automatically groups related rows together to form complete objects.
Standard Grouping Methods
The system uses identifying columns to group rows together, following this priority order:
Primary ID: Uses the main identifier (Product ID, Order ID, Customer ID, etc.) to group rows
Secondary Identifier: Falls back to handles, names, or titles depending on the data type
Additional Identifiers: May use other unique fields like email addresses (customers) or SKUs (product variants)
Fallback Grouping
When your spreadsheet contains no identifying columns, Altera uses these fallback methods to ensure compatibility with all file formats:
Top Row Column: If a "Top Row" column is present with TRUE/FALSE values, rows are grouped using these markers. Each group of rows between TRUE values becomes a single object.
All Rows Together: If no identifying columns or Top Row column exists, all rows in the spreadsheet are grouped together as a single object (matching Matrixify behavior).
Examples
Product with variants using ID:
ID | Title | Variant SKU 12345 | T-Shirt | SHIRT-RED-S 12345 | T-Shirt | SHIRT-RED-M 12345 | T-Shirt | SHIRT-RED-L
Product with variants using Top Row:
Top Row | Title | Variant SKU TRUE | T-Shirt | SHIRT-RED-S FALSE | T-Shirt | SHIRT-RED-M FALSE | T-Shirt | SHIRT-RED-L
This fallback system ensures that exported files from other systems (including Matrixify) can be imported without requiring any reformatting.
Import tips
Keep the first row as headers exactly as in the reference.
Remove empty columns, hidden formulas, and unused sheets before saving.
Save CSVs with UTF‑8 encoding.
Preview data in Altera before clicking Start import to catch header or encoding issues.