For accountants, online sellers and developers
Open, filter and split multi-GB CSV files without uploading anything.
Accounting export, product catalogue or customer list too big for Excel? CSV Géant streams your file inside your browser: instant preview, row count, filter, deduplicate, sort, split into several files and export in the format Excel expects (UTF-8 with BOM, your choice of delimiter).
- No file is ever uploaded
- No account, no install
- Free up to 100,000 rows per export; beyond that, Pro licence, €29 paid once
Tool
I already have a key
Pricing
Free
0 €
- Preview, delimiter and encoding detection
- Row count, any file size
- Filter, deduplicate, sort, split
- 100,000 exported rows per operation
Pro
29 € one-time, lifetime
- Unlimited exported rows
- Everything in Free
- Updates included, no subscription
Secure checkout by Gumroad, which emails you a licence key. 14-day refund.
Have a licence key?
Limits, honestly
- Tested sizes (Chrome 154 on Windows 11, 16 GB RAM, automated test): a 2.2 GB file (22 million rows) counted in 16–23 s, deduplicated and split into 21 Excel files written to a folder in 1 min 40, filtered and deduplicated as a download (0.8 GB output) in 1 min 03; a 548 MB file counted in 4–5 s, 2 million rows sorted in 15–24 s. Timings depend on your machine. Streaming has no theoretical ceiling beyond 2.2 GB, but it has not been measured yet.
- Browsers: tested in Chrome. Edge (same engine) should behave the same; Firefox and Safari are not tested yet.
- Memory: count, filter and split read the file in 8 MB blocks. Deduplication keeps 16 to 32 bytes per distinct row (≈ 256 MB for 10 million). Sorting keeps the whole result in memory: 3 million rows or 600 million characters at most.
- Download: the output file is assembled by the browser first. For results over 1 GB, choose “Write directly to a folder” (Chrome, Edge).
- Format: standard CSV (RFC 4180): doubled quotes and line breaks inside quotes are supported. A single record over 16 MB (unclosed quote) stops processing with a message.
FAQ
Is my file uploaded anywhere?
No. Your browser reads the file on your computer and writes the output files there. The server only receives anonymous counters (one visit, one export) and, if you enter one, your licence key so it can be checked with Gumroad. Try it: once the page has loaded, go offline and the tool keeps working.
Why does Excel garble my CSV (accents, everything in one column)?
Excel only recognises UTF-8 when the file starts with a BOM, and expects the delimiter of your regional settings (semicolon in French, comma in English). CSV Géant writes UTF-8 with BOM and lets you pick the delimiter.
My file has more than 1,048,576 rows, Excel's limit.
Choose “Files that open in Excel”: the result is split into files of 1,048,575 rows, each with the header row repeated.
My export is ANSI / Windows-1252.
The encoding is detected automatically (UTF-8 or Windows-1252, plus UTF-16 with BOM). You can force it in the “Encoding” list. Output files are always UTF-8.
What does Pro add?
The free version exports up to 100,000 rows per operation (the tool tells you how many rows the full result would contain). The Pro licence, €29 one-time, removes that limit in the browser where you enter the key. Preview and counting are free and unlimited.
New computer or browser?
Enter your licence key (emailed by Gumroad) again on the new device.
Can I get a refund?
Yes, within 14 days of purchase, no questions asked: write to the address given in the terms of sale (in French).