EasyXLS

Tips for reading large Excel file in .NET, Java and other programming languages

EasyXLS™ library allows you to read large data from Excel file with fast reading time. The supported Excel file formats are XLSX, XLSM, XLSB and XLS.

If not familiar with EasyXLS Excel library, read first how to read data from Excel file in .NET and how to read data from Excel file in Java.

The below 5 tips will guide you to read large Excel files.

1. Do not load the entire Excel file, if only data needed

Avoid the usage of the methods that load the entire Excel file structure and use the methods that allows reading only the data from the sheets.

C#.NET
VB.NET
C++
Java
PHP
ASP
VB6
VBS
Coldfusion
Python

2. Read only ranges of Excel cells, if not entire sheet data needed

Try to read only the data that is required and avoid reading excessive data. EasyXLS provides methods that permit reading data only from ranges of cells.

C#.NET
VB.NET
C++
Java
PHP
ASP
VB6
VBS
Coldfusion
Python

3. Recommended file formats

XLSB and XLS file formats are binary files and therefore are faster to read by default. EasyXLS recommends to use these file formats for better performances.

4. Read data step by step

If the Excel file is very large, the DataSet might be too big in memory when reading the entire data from the Excel file. A solution is to read data range by range and dispose the DataSet and other resources after every use.

5. Java memory heap

When using Java programming language, it is recommended to add an extra parameter when running your application. JRE uses 64M of memory by default and your computer performances don't count. You need to increase the memory heap size by using -mx option (run your application using "java -mx512m").


Available for: Professional, Excel Reader
Go to top

EasyXLS Excel libraries:

.NET
.NET Excel Library
full .NET version to import, export or convert Excel files
.NET Excel Reader
.NET version to read and import Excel files
COM+ Excel Library
full COM+ version to import, export or convert Excel files
COM+ Excel Reader
COM+ version to read and import Excel files
-
Java
Java Excel Library
full Java version to import, export or convert Excel files
Java Excel Reader
Java version to read and import Excel files
Download EasyXLS™ Excel Library for .NET and Java

File formats:

Office 365
MS Excel 2021 - 2024
MS Excel 2007 - 2019
MS Excel 97 - 2003
XLSXXLSMXLSBXLS
XMLHTMLCSVTXT