About CSV Viewer Online
This CSV viewer opens on the Preview tab, which shows your data as a table with a filter box above it and headers you can press to sort. It is free, needs no sign-up and runs in your browser, so nothing you enter is uploaded.
Drop or paste a .csv, .tsv or .txt file of up to 20 MB. The table shows 50 rows per page with Previous and Next buttons, and the line under it reads "Rows 1 to 50 of N", where N counts the rows that match your filter. The filter box keeps rows where any cell contains your text, ignoring letter case, and waits a moment after you stop typing. It does not use column-specific queries or regular expressions.
Pressing a header sorts by that column and pressing again reverses the order. Numeric values sort as numbers, so 9 comes before 10, and anything else sorts as text. Quoted fields with commas or line breaks stay in a single cell, and two columns with the same header stay separate. The table scrolls sideways inside its own frame on a phone. Viewing only: the file cannot be edited or saved back. Use the Summary view when you need figures for all rows.
How to use CSV Viewer Online
- Drop a file onto the box, tap it to choose one, or paste a copied file. CSV, TSV, TXT, XLSX and XLS files up to 20 MB are accepted. To paste text instead, use the text box below it.
- For a workbook with several sheets, choose the sheet from the Sheet list that appears.
- Read the Overview: rows, columns, missing values, the delimiter and any columns that held stray values.
- Open Summary for per-column statistics, then Profile for types, percentage missing, distributions and the stray values.
- Open Correlation to see how the numeric columns move together, with blue for positive and red for negative.
- Open Preview to read the rows, 50 per page. Type in the filter box to keep matching rows, and press a column header to sort.
- Open Chart, pick a chart type and a column (two for a scatter plot), or press Open Chart Maker for more chart types.
- Press the download button in Summary to save the column statistics as a CSV file.
Features
- Open .csv, .tsv, .txt, .xlsx and .xls files up to 20 MB, or paste a file or text.
- Parsing runs in a Web Worker for files and pastes, never on every keystroke. The paste box waits half a second after you stop typing.
- Automatic delimiter detection among comma, semicolon, tab and pipe, with quoted fields and a leading byte-order mark handled.
- Excel support through SheetJS, loaded only when a workbook is opened, with a sheet picker.
- Columns are tracked by position, so two columns with the same header stay separate. The second one is shown as "name (2)".
- Majority-type inference: a column is numeric when 95 percent or more of its non-missing values are numbers, and a date column on the same rule. Stray values are listed.
- Missing values recognised as empty cells, NA, N/A, NaN, null, none, nil, a single or double dash and #N/A, in any letter case.
- Per-column count, missing, unique, mean, median, quartiles, minimum, maximum and sample standard deviation.
- Minimum and maximum are found with a loop, so columns of hundreds of thousands of values are safe.
- Pearson correlation matrix of the numeric columns (the first 30 when there are more), using only rows where both values are present.
- Paged preview, 50 rows per page, with a filter and sortable headers, inside a scroll area that works on a phone.
- Chart builder: bar chart of counts, histogram and scatter plot, plus a link to Chart Maker.
- Download of the per-column summary as a CSV file.
Worked examples
The sample data filtered with "dhaka" gives 2 rows remain, Alice and Carol. The line reads Rows 1 to 2 of 2.
The match is case-insensitive and looks in every column.
The sample data sorted by score, high to low gives Carol 95, Alice 88, Eve 79, Bob 72, Dan 64.
Dan has no score in the sample, so that cell is blank.
A file with 120 rows gives Three pages: rows 1 to 50, 51 to 100 and 101 to 120.
Privacy: how it works
- Files are read by your browser and parsed by JavaScript in a worker on this page. The contents are not sent to Ulkaa or to any other server. The Excel reader is part of this site and loads from it, not from a third party, and only when you open a workbook.
- Nothing is stored. Reloading the page clears everything. The summary CSV is created on your device when you press the download button.
Tips
- If a column you expected to be numeric shows as text, open Profile and read its stray values. A currency symbol, a decimal comma or a word is usually the cause.
- Check the missing count before looking at averages. A mean computed from only 60 percent of the rows can mislead.
- A correlation matrix only covers numeric columns. Encode a yes or no column as 1 and 0 first if you want it included.
- Quote any field that contains your delimiter, such as "1,200" in a comma file, so the row keeps its column count.
- For a very large file, open it instead of pasting it. The paste box is meant for small pastes.
- Delimiter detection looks at the first five lines. Make sure they use the same separator as the rest.
Frequently asked questions
Is it really free?
Yes. There is no price, no trial and no credit card. Ulkaa Tool does the work with your own device, so there is no server bill to pass on to you.
Do I need an account?
No. There is no sign-up and no login. Open the page and use it. An Ulkaa account is not needed for anything on this tool.
Does it run in my browser?
Yes. Your data are processed by code running in your browser tab, on your own device.
Is my data uploaded?
No. Your data are never sent to Ulkaa or to anyone else. You can check this yourself by watching the Network tab in your browser developer tools while you use the tool.
How many rows does the viewer show?
Fifty per page. Use Previous and Next to move through the rest. The line under the table shows which rows you are on and how many match your filter.
Can I edit the CSV or save changes?
No. The viewer is read-only. Edit the original in a spreadsheet or text editor.
Does it sort numbers correctly?
Yes, when both values being compared are numbers they are compared as numbers. Otherwise they are compared as text.
More CSV, Excel and Data Analyzer pages
- CSV, Excel and Data AnalyzerOpen a CSV, TSV or Excel file, or paste text, and profile every column: types, missing values, statistics, charts and correlations.
- CSV Analyzer OnlinePer-column statistics for a CSV file, in the Summary view.
- Excel Data AnalyzerOpen an Excel workbook, pick a sheet and get column statistics.
- Excel Viewer OnlineOpen an Excel file, choose a sheet and read it as a table.
- Correlation Matrix OnlineA Pearson correlation matrix of every numeric column in your data.
- Data Profiling Tool OnlineA column-by-column profile of a CSV, an Excel sheet or a pasted table.