How to open a large CSV file
Drop the CSV on this page. Your browser reads it on your device and shows every row, even millions, with smooth scrolling. Search every column, add include and exclude filters, tick the values you want in the side panel, then export the rows you found.
Open the file
Drop it on the page or choose it. The delimiter (comma, semicolon, tab or pipe), the text encoding and the header row are found for you; change them under File if the columns look wrong.
Find the rows
Type in the search box to search every column as you type. Add Include and Exclude filters for the rows you want and the ones you do not, in every column or in one. Click a row to see all its fields and filter on any of them.
Count and narrow by value
Values in the side panel lists the different values of a column with how many rows have each, among the rows your other filters leave. Untick values to hide their rows, or click Only.
Export
Export saves the rows you see, with the columns you kept, as a new CSV.
Include, exclude and values
Every filter narrows the rows together. Include keeps rows that have a match; Exclude removes rows that have one. With two or more Includes you choose whether a row needs all of them or any one, so failed and warning as Any shows both. Each filter can look in every column or in one; pick it in the list next to the box.
The value list is the quickest way through a log: open a Status column and you see at once how many rows succeeded, failed or were skipped. The counts follow your other filters, so with Failed ticked in Status, the Error code column shows which errors caused the failures and how often.
Each column's header has a menu (the arrow, or a right click): sort, filter the column by a value or a range (greater than, between two dates, not empty, and more), compare it with another column in the same row, see its values and counts, or hide it. Comparing columns finds rows such as those where Finished is before Started, or Size is greater than Quota.
Columns lets you hide what you do not need. Click a column's name to sort by it: numbers sort as numbers and dates as dates, with empty cells last.
Filter syntax
| Type | Matches |
|---|---|
denied | Cells containing "denied", in any case |
=Failed | Cells that are exactly "Failed" |
^/sites/HR | Cells starting with /sites/HR |
.pdf$ | Cells ending with .pdf |
>1000000 <=50 | Numbers greater than, or at most. Dates work too: >2026-09-14 12:00 |
/^E4\d\d$/ | A regular expression (case-insensitive unless you add flags) |
"" | Empty cells |
>[Duration] =[Owner] !=[Owner] | Compares with another column in the same row: rows where the chosen column is greater than Duration, the same as Owner, or different from it. Pick the column in the list next to the box |
"=x" | Quotes take the text as it is: cells containing =x |
When a CSV is too big for Excel
Excel stops at 1,048,576 rows and Google Sheets at 10 million cells, so the exports that matter most, such as migration logs, audit logs, transaction histories and database dumps, often cannot be opened at all. This viewer has no row limit of its own. Filter down to the rows you need and export them, and the smaller file opens anywhere.
Where the file goes
Nowhere. The page reads the file with your browser's own file reader and keeps it in memory until you close the tab or open another file. There is no upload and no server that could see it, which matters for logs full of names, email addresses and file paths.
Limits and formats
| Size | Hundreds of megabytes and millions of rows; it needs about one and a half times the file's size in memory. A file too big for that (or over 4 GB) can still be opened in part: the first gigabyte, about 5 million rows |
|---|---|
| Speed | A 2 million row, 390 MB log opens in a few seconds on a laptop; a search over all of it takes about half a second |
| Formats | CSV, TSV and text with any one-character delimiter; quoted cells with commas, quotes and line breaks (RFC 4180); Excel's sep= line |
| Encodings | UTF-8 (with or without BOM), UTF-16, Windows-1252, and others to choose under File |
| Uneven rows | Short rows get empty cells; extra fields stay in the last column, so nothing is lost |
| Value counts | For columns with up to 300,000 different values; others are filtered with Include and Exclude |
Questions
Open it here. Excel stops at 1,048,576 rows; this viewer reads the file in your browser and shows every row. Filter it down and export the rows you need as a smaller CSV that Excel can open.
No. It is read by your browser on your own device and nothing is sent anywhere. You can check in the browser's network tools: opening a file makes no requests.
Files of several hundred megabytes and millions of rows open in seconds. The limit is the memory your browser may use, about one and a half times the file's size. When a file is too big for that, or over 4 GB, the viewer says so and offers to open its first gigabyte, about 5 million rows.
The delimiter was guessed wrong, which can happen with very short files. Open File in the side panel, pick the delimiter and press Read the file again. Strange characters such as é mean the wrong text encoding: pick Windows-1252 or UTF-8 there.