File import details (encoding, sheets, JSON shapes, size limit)

Updated September 25, 2026Markdown

This article covers the technical details behind a file import — what happens automatically, and what you can adjust. For the step-by-step import flow, see "Create a list and import a file."

Encoding and delimiters are automatic#

ListPlus detects your file's character encoding automatically (falling back through UTF-8, ISO-8859-1 and Windows-1252 if needed), so accented or non-Latin characters from older exports come through correctly without you choosing an encoding. For CSV, TSV and TXT files, the delimiter (comma, semicolon, tab or pipe) is also detected automatically — there's no manual picker for either setting.

Excel: picking a sheet or table#

If your Excel file (.xlsx, .xlsm, .xls) has more than one worksheet with data, or more than one named table, a Select a Table or Worksheet step lists them so you can pick which one to import. With a single sheet, it's imported directly. If a worksheet has no named tables, a note says the entire sheet will be imported; a worksheet with no data is flagged as empty so you don't end up with a list that has no columns.

JSON shapes ListPlus understands#

The straightforward case is a JSON array of objects, one object per row — that's what ListPlus expects by default. It also handles a few looser shapes: a plain array of values (each value becomes a row in a value column, plus an original_index column), an array that is at least 80% objects (the objects are imported, the rest skipped), and a single JSON object with an array of objects as one of its top-level properties (the first such array is imported). A JSON value with no array at the top level, such as a single flat object, can't be turned into a list.

Size limit and formats#

Every file type — Excel, CSV, TSV, TXT and JSON — is limited to 100 MB, checked as soon as you select the file, both in your browser and on the server. There's no separate cap on row count in the file itself; only your plan's overall record limit applies once the rows are imported (see "What is the record limit?").

Dropping a file, and skipping a column#

Dropping a .csv, .xlsx, .xls or .json file anywhere on the Home page jumps straight into the New List wizard with that file attached — an unsupported file type shows "Please select a CSV, Excel, or JSON file" instead. In the preview step, if you don't want a column imported, click the three-dot (⋯) button in that column's header and choose Ignore column — the column is left out of the list ListPlus creates.

Related topics: create-list-and-import-file · record-limit · column-detection · linkedin-imports.

FAQ#

Do I need to tell ListPlus my file's character encoding?#

No — ListPlus detects the encoding automatically (falling back through UTF-8, ISO-8859-1 and Windows-1252), so there's no manual setting to get wrong on older exports with accented characters.

Does ListPlus know which delimiter my CSV or TSV file uses?#

Yes, it detects the delimiter — comma, semicolon, tab or pipe — automatically from the file; TXT files are parsed the same way as CSV and TSV.

My Excel file has multiple tabs — which one gets imported?#

If your file has more than one worksheet with data, or more than one named table, a Select a Table or Worksheet step lets you pick which one to import; with a single sheet, it's imported directly, and if no named tables are found, the whole sheet is imported instead.

What happens if I try to import an empty worksheet?#

ListPlus flags it as an empty worksheet so you're not left with a list that has no columns; pick a different sheet or table in the same step.

What JSON structure can I import?#

A JSON array of objects — one object per row — is the standard shape. ListPlus also accepts a single object with an array of objects at the top level (it imports the first one) and an array that is at least 80% objects (the objects are imported, the rest skipped); a JSON value with no array at the top level can't become a list.

Is there a file size limit for imports?#

Yes, 100 MB per file, for every supported format (Excel, CSV, TSV, TXT and JSON) — checked as soon as you select the file. There's no separate row-count limit on the file itself, only your plan's overall record limit once the rows are in a list.

Which files can I drop onto the Home page?#

Dropping onto Home accepts .csv, .xlsx, .xls and .json files. For .xlsm, .tsv or .txt files, click New List and choose the file under Import a file. Dropping them on Home shows "Please select a CSV, Excel, or JSON file".

How do I stop one column from being imported?#

In the preview step, click the three-dot (⋯) button in that column's header and choose Ignore column — it's left out of the list ListPlus creates, and the rest of your file imports normally.