Types of files

Rowboat can open comma-separated value (CSV) files and tab-separated value (TSV) files.

Rowboat can also open Excel files (.xls and .xlsx). If the file has multiple sheets, Rowboat will ask for the specific sheet that you would like to open.

We also offer browser extensions for Chrome and Firefox. Both extensions can open HTML tables and links to .csv, .tsv, and .xls spreadsheets in your browser with a simple right click. Just locate the dataset you want to examine, right click, and select “Open Table in Rowboat” to start exploring.

With the Chrome, you can also easily view Google Sheets spreadsheets in Rowboat without having to download the file first. With your spreadsheet open, click the Chrome extension, and your spreadsheet will automatically open up in Rowboat.

File size

The browser version of Rowboat can currently work with files up to approximately 800 MB, depending on your machine.

Rowboat Desktop can open files over 10GB in size.

Look out for upcoming improvements to memory in the browser, as well as other options for working with larger files.

Encodings

Rowboat does its best to automatically detect the encoding of the file, but it may not always be right.

To change the encoding used to read a file, look for the encoding dropdown at the bottom of the window, and choose between the following options:

• ASCII
• UTF-8
• UTF-8 (with BOM)
• UTF-16
• UTF-16 (Little Endian)
• ISO 8859-1
• Windows CP1252
• Mac Roman

Note that when exporting or saving a file, it will be saved in UTF-8 format, regardless of the original format.

Column data types

Rowboat distinguishes between the following column data types:

• Text
• Integer
• Decimal
• Time

Rowboat does its best to automatically detect column data types. To change the data type of a column, use the data type dropdown in a column to switch to another data type.

Parsing numbers

Rowboat supports basic handling of integer and decimal entries containing the following symbols:

• $ and € symbols at the beginning of entries.
• , from the interior of entries.
• % at the end of entries.

Currency

Rowboat currently detects the dollar symbol ($) and the Euro symbol (€). Negative currency amounts are not supported at this time.

Date and time formats

Rowboat automatically detects the following date and time formats. Additional timestamps formatted in strptime date notation are also supported when manually entered using the “Set Format” option for the column, in the data type dropdown.

Certain formats will not automatically be detected, such as %Y on its own, or %Y%m%d, because these cannot be distinguished from numbers that happen to have the same number of digits. To properly parse the latter, you must manually enter %Y%m%d as the format, which will be changed to %E4Y%m%d behind the scenes, specifying a 4-digit year. Years that are three digits (as in AD 476) or five or more digits are also supported by the time parser, so it's necessary to differentiate in the formatting to match properly.

More of these extended formats can be found in the Google BigQuery documentation.

Also note that time formats that use %- syntax are not supported. (They are for formatting without zero padding, so the - syntax is not relevant in Rowboat, which is focused on parsing the data.)

Header row detection

Rowboat attempts to automatically detect whether a file has a header row. To change this, toggle headers on or off in the bottom bar of the app.

Rowboat does not currently support files with multiple header rows. However, additional rows can be deleted by hiding rows and then turning on headers for the last remaining row.