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XLS to XLSX — Format Comparison & Online Converter

Fast, instant XLS to XLSX conversion. No signup required. Just drop your .xls file and get .xlsx in seconds.

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Some metadata may not survive

Your XLS file may contain OLE properties metadata. XLSX has limited or no support for these metadata types. Location data (GPS), camera settings, and color profiles may be stripped during conversion.

还在为那些老旧的XLS文件发愁吗?它们不仅打开速度慢,在手机上查看更是常常排版错乱,分享到微信群里也显得格格不入。特别是在我们快节奏的生活里,无论是处理工作报表、记录游戏数据,还是和朋友们共享一份购物清单,大家都更偏爱那种即点即开、格式现代的体验。将XLS转换成XLSX,就像给你的数据文件做了一次彻底的升级,瞬间变得轻盈、兼容性更强,无论是用电脑还是手机,都能顺畅无阻地查看和编辑。告别那些过时的烦恼,让你的表格文件焕发新生,轻松融入当下的数字生活。

  • 公司财务报表微信分享
  • 手游玩家装备数据整理
  • 家庭旅行预算手机查阅

在大陆、台湾和新加坡地区,由于移动办公和社交分享的普及,XLSX格式因其更好的移动设备兼容性和对新功能的强大支持,已成为主流选择,更符合现代用户的使用习惯。

About XLS to XLSX Conversion

XLS (introduced 1987) and XLSX (introduced 2006) are both spreadsheet formats, but they differ in important ways. XLS is the legacy Excel format (pre-2007) — still encountered in business workflows. XLSX is Microsoft Excel's modern format supporting formulas, charts, and multiple sheets.

Full Name: XLS uses Microsoft Excel Legacy, while XLSX uses Microsoft Excel Spreadsheet. Compression: XLS uses None (uncompressed), while XLSX uses Lossless. Typical File Size: XLS uses 50 KB–50 MB, while XLSX uses 50 KB–50 MB.

When you convert XLS to XLSX, the goal is to upgrade to a modern format. Converting XLS to XLSX maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.

Your XLS file is decoded and re-encoded as XLSX. The conversion involves 4 steps: (1) your xls file is uploaded and the format is validated, (2) the file content is decoded into its raw representation, (3) the data is re-encoded in xlsx format with optimal settings, (4) the converted file is ready for download.

CocoConvert's converter handles the entire pipeline server-side using FFmpeg, Sharp, and qpdf — battle-tested libraries used by streaming platforms and enterprise tools. Files are encrypted in transit and deleted within 24 hours.

This conversion is ideal when you You need maximum device and software compatibility. For the opposite direction, CocoConvert also supports XLSX to XLS conversion.

How to Convert XLS to XLSX

  1. 1

    Upload .xls file

    Select your XLS file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.

  2. 2

    Choose .xlsx

    Set XLSX as the output format. The converter uses optimal settings based on the XLS→XLSX conversion profile.

  3. 3

    Convert

    The server-side engine decodes your XLS file and re-encodes it as XLSX. Processing time depends on file size and complexity.

  4. 4

    Download result

    Grab your converted .xlsx file. Multiple output files can be downloaded together.

What Happens When You Convert XLS to XLSX

Your XLS file is decoded and re-encoded as XLSX.

1

Your XLS file is uploaded and the format is validated

2

The file content is decoded into its raw representation

3

The data is re-encoded in XLSX format with optimal settings

4

The converted file is ready for download

XLS vs XLSX — Detailed Comparison

Feature.XLS.XLSX
Full NameMicrosoft Excel LegacyMicrosoft Excel Spreadsheet
CompressionNone (uncompressed)Lossless
Typical File Size50 KB–50 MB50 KB–50 MB
Platform SupportUniversalUniversal
Browser Supportnonenone
Year Created19872006
Open StandardNoYes

Should You Convert XLS to XLSX?

When to Convert

  • You need maximum device and software compatibility

Common Mistakes When Converting XLS to XLSX

"XLSX will be smaller than my XLS file"

XLSX uses lossless compression, so the output file is often larger than a lossy XLS. If you need a small file, XLSX may not be the right choice.

Frequently Asked Questions

What is the difference between XLS and XLSX?

XLS is the legacy Excel format (pre-2007) — still encountered in business workflows. XLSX is Microsoft Excel's modern format supporting formulas, charts, and multiple sheets. Full Name: XLS uses Microsoft Excel Legacy, while XLSX uses Microsoft Excel Spreadsheet. Compression: XLS uses None (uncompressed), while XLSX uses Lossless. Typical File Size: XLS uses 50 KB–50 MB, while XLSX uses 50 KB–50 MB.

Does XLS to XLSX conversion affect quality?

Converting XLS to XLSX maintains high quality with CocoConvert's optimised encoder settings.

Which format has better compression, XLS or XLSX?

XLS uses none compression. XLSX uses lossless compression. The better choice depends on whether you prioritize file size or quality.

How long does XLS to XLSX conversion take?

Most conversions finish in seconds. Larger files or complex spreadsheet content may take 10–30 seconds. CocoConvert processes files in parallel for batch jobs.

Is XLS or XLSX better for long-term storage?

XLSX is better for archival since it preserves all original data.

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