RowlodeHow-to guides for CSV files
Each guide starts with the free fix in Excel or the command line, then shows where Rowlode is quicker.
Excel opens CSV in one columnWhy Excel puts every CSV value in column A – the list separator of your region vs the file's delimiter – and four fixes, from Text to Columns to a sep= line.Keep leading zeros in a CSVExcel turns 00123 into 123 when it opens a CSV. The Automatic Data Conversion setting, the import-as-text method, and how to hand over files that keep zeros.Long numbers become 1.23E+15Excel stores only 15 significant digits, so card numbers, IBAN-like IDs and order numbers in a CSV turn into 1.23E+15 and lose digits. How to keep them exact.Garbled characters (é) in ExcelAccented or non-Latin characters break when Excel opens a UTF-8 CSV without a BOM (é, ü, ש). How to open it correctly and how to save a CSV Excel reads right.Over 1 million rows: Power QueryExcel's sheet limit is 1,048,576 rows, but Power Query can load bigger CSVs into the Data Model for PivotTables. Steps, limits, and when another tool is easier.Convert a large CSV to JSON / NDJSONTurn a big CSV into a JSON array or NDJSON for APIs, MongoDB or BigQuery – which format to pick, type pitfalls, and a no-code way that works offline.Count rows in a large CSVCount records in a CSV too big for Excel: PowerShell, wc -l, Python – why line counts overstate rows when fields contain line breaks, and an exact method.
Converter pages
Open a CSV too big for ExcelSplit a CSV into multiple filesExcel row limit (1,048,576)Remove duplicates from a CSVFilter a large CSVMerge CSV files into oneSemicolon to comma, fix encodingLarge CSV to XLSX, multiple sheets
Have a big or messy CSV? Rowlode opens CSV files with millions of rows (multi-GB) in your browser, reading them from disk – filter, remove duplicates, sort, fix delimiter and encoding, and export CSV, Excel (split under the row limit), TSV, JSON or NDJSON. Nothing is uploaded. Viewing, filtering and dedupe are free; each export holds the first 10,000 rows until you buy a $12 lifetime license.
Sources and product names: Microsoft Excel and Power Query are trademarks of Microsoft; Google Sheets is a trademark of Google. Rowlode is independent and not affiliated with them.