Questions and answers

Only where you change them. Open a file and save it without edits and you get the same bytes back: the same separator, quoting, encoding, byte-order mark and line endings. Automated tests check it for every preset, for Windows-1252 and UTF-16 files, for values with line breaks inside and for a file of a million rows.

Because a value is kept as the text that was in the file. 00731 is shown and saved as 00731; it is only treated as a number where you ask for arithmetic — in the status bar, in a sort, in SQL. More on leading zeros.

Formats with real types store numbers the way any such store does: 1234.50 typed into a CSV becomes 1234.5 in a JSON number or a database column. Delimited text, Excel and OpenDocument keep the text exactly as written.

The save stops and tells you which character, in which cell — a € in a Latin-1 file, say. You can change the value or save in another encoding. It is never written as a question mark.

Delimited text of every kind, fixed-width text and log files; Excel workbooks old and new (.xlsx, .xlsm, .xls, .xlsb), OpenDocument, HTML and Markdown tables; JSON, JSON Lines, YAML, XML, TOML, GeoJSON, property lists, BSON and MessagePack; Parquet, Avro, ORC, Arrow and Feather, Delta Lake and Iceberg tables, Python pickles and SQLite; SPSS, Stata, SAS, R, MATLAB, HDF5 and NetCDF; EBCDIC mainframe files with a COBOL copybook, bank records, vCards and your Mac's Contacts. All formats.

Yes. Saving an .xlsx puts the workbook back as itself: its other sheets, formats and charts are kept, and only the rows of the sheet you edited are replaced — a formula there is saved as the value it last calculated. A format the app reads but does not write back in place — an old .xls, an .ods, a SQLite database, a Parquet file — is saved to a copy, and the original stays as it was. Save As converts between any of them.

Millions of rows. The table is held in memory as compact UTF-8, so your Mac's memory is the limit rather than a row count: a file of a gigabyte — sixteen million rows — is held in about 1.6 GB. For a file too big to want whole, File ▸ Open Part of a File opens its beginning, its end or a stretch in between as a table of its own. Opening large files.

Yes — File ▸ Open from a Link. Only an address you typed or picked from the list is fetched, and only over http or https.

No. Reading, editing, SQL, macros and exports all happen on your Mac.

On its own, two things. It checks its trial or licence now and then, with a one-way hash of the Mac's hardware identifier that says nothing about the Mac beyond being it. And once at launch and once a day it sends a usage count made of a random number, the app and macOS versions, your region and your first language — turn that off in Settings ▸ Info and it is not sent. Never your account, never anything about a file. Everything else only when you ask: opening a link, asking a web service about each row, signing in, checking for updates (off unless you switch it on). Privacy.

Yes. Files never need the network, and the licence is checked now and then and keeps working in between. A Mac that has not been online for a fortnight goes on reading and exporting, and edits again as soon as it has asked once.

Seven days without an account; fourteen from the same start with a confirmed email address. Every feature is included and no card is needed. A new version can be tried for seven days of its own. When a trial ends, the app still opens, reads, sorts, filters, queries and exports your files; only editing and saving wait for a licence.

The price is announced with the public release. Pricing.

Macs with macOS 14 Sonoma or later.