Read genuine legacy binary XLS worksheets, preview cell values and export UTF-8 CSV with safe quoting, delimiter and formula-injection controls.
Drag and drop one or more files, or choose files from your device.
Supported: .xls · up to 10 sources · 10 MiB per source. Existing codec, duration, pixel and memory limits apply.
Choose a worksheet separately for each source after inspection. Existing cached values, cell formatting, quoting and safe-export rules apply. Worksheets are never silently merged.
Enter your values locally; no inputs are uploaded.
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Review the explanation, copy supported outputs or reset the workspace.
Choose a supported local source, review the compatibility notes and settings, convert, inspect the verified preview and download the result.
Read genuine legacy binary XLS worksheets, preview cell values and export UTF-8 CSV with safe quoting, delimiter and formula-injection controls. Supports OLE-contained BIFF5/BIFF8 XLS, not renamed XLSX, raw BIFF2, encrypted workbooks or universal Excel features. Select one worksheet per CSV. Values preserve stored text IDs and leading zeros; dates use ISO-style serial conversion, numbers use their numeric value, booleans use TRUE/FALSE and errors use Excel error text. Formulas export cached values only, with warnings for missing/stale caches; nothing is recalculated. Safe export prefixes potentially executable text (=,+,-,@ after whitespace) with an apostrophe; numeric negative cells remain numeric. CSV cannot retain styles, formulas or multiple sheets. Spreadsheet auto-type inference can still alter text IDs on reopening. Limits: 10 MiB, 32 sheets, 10,000 rows/256 columns/100,000 grid cells per sheet, 8 MiB CSV.
File bytes, filenames and source content remain in browser memory. They are not uploaded to conversion endpoints, included in analytics, logged or persisted by this tool. Reset/unmount cancels pending work and revokes owned preview URLs; downloads require explicit actions. Ordinary page requests may still be logged.
No. It checks the OLE container signature and a binary Excel Workbook/Book BIFF stream. The supported subset is BIFF5/BIFF8 XLS; encrypted workbooks, raw BIFF2 and renamed ZIP-based XLSX files are rejected.
Yes. Detected worksheet names, row/column counts and a bounded cell preview appear before conversion. Select one worksheet per CSV. CSV cannot contain a multi-worksheet Excel workbook or retain its styling.
Text cells retain their stored strings, including leading zeros and multiline content. Numeric cells export numeric values, dates use ISO-style serial conversion, booleans use TRUE/FALSE and errors use Excel error text. Spreadsheet auto-type inference can still change IDs when reopening a CSV.
No. Formula cells export available cached values with a warning that caches can be stale. Missing cached values export empty with a warning where represented by the parser. Formula expressions and macros are never executed or recalculated.
Safe export is enabled by default and prefixes risky text starting with =, +, - or @ after whitespace/control characters with an apostrophe. Stored numeric negative values remain numeric. The apostrophe may be visible in non-spreadsheet CSV consumers, so the policy is disclosed rather than hidden.
Choose comma, semicolon or tab. Values containing the delimiter, quotes or line breaks are correctly quoted, and embedded quotes double. Output is UTF-8 with an optional BOM and CRLF row endings. Workbook and output-size safeguards are shown in the workspace.
Read genuine legacy binary XLS worksheets, preview cell values and export UTF-8 CSV with safe quoting, delimiter and formula-injection controls.
Supports OLE-contained BIFF5/BIFF8 XLS, not renamed XLSX, raw BIFF2, encrypted workbooks or universal Excel features. Select one worksheet per CSV. Values preserve stored text IDs and leading zeros; dates use ISO-style serial conversion, numbers use their numeric value, booleans use TRUE/FALSE and errors use Excel error text. Formulas export cached values only, with warnings for missing/stale caches; nothing is recalculated. Safe export prefixes potentially executable text (=,+,-,@ after whitespace) with an apostrophe; numeric negative cells remain numeric. CSV cannot retain styles, formulas or multiple sheets. Spreadsheet auto-type inference can still alter text IDs on reopening. Limits: 10 MiB, 32 sheets, 10,000 rows/256 columns/100,000 grid cells per sheet, 8 MiB CSV.
Start with the original supported source. Review detected content and the output settings before converting. Inspect actual output previews, page breaks, text, table values and transparency as applicable. Download only after checking warnings and the displayed format/size information.
No. It checks the OLE container signature and a binary Excel Workbook/Book BIFF stream. The supported subset is BIFF5/BIFF8 XLS; encrypted workbooks, raw BIFF2 and renamed ZIP-based XLSX files are rejected.
Yes. Detected worksheet names, row/column counts and a bounded cell preview appear before conversion. Select one worksheet per CSV. CSV cannot contain a multi-worksheet Excel workbook or retain its styling.
Text cells retain their stored strings, including leading zeros and multiline content. Numeric cells export numeric values, dates use ISO-style serial conversion, booleans use TRUE/FALSE and errors use Excel error text. Spreadsheet auto-type inference can still change IDs when reopening a CSV.
No. Formula cells export available cached values with a warning that caches can be stale. Missing cached values export empty with a warning where represented by the parser. Formula expressions and macros are never executed or recalculated.
Safe export is enabled by default and prefixes risky text starting with =, +, - or @ after whitespace/control characters with an apostrophe. Stored numeric negative values remain numeric. The apostrophe may be visible in non-spreadsheet CSV consumers, so the policy is disclosed rather than hidden.
Choose comma, semicolon or tab. Values containing the delimiter, quotes or line breaks are correctly quoted, and embedded quotes double. Output is UTF-8 with an optional BOM and CRLF row endings. Workbook and output-size safeguards are shown in the workspace.
Conversion uses bounded browser memory and disposable processing Workers. HTML layout uses a sandbox with scripts and remote assets disabled. Source files and filenames stay out of logs, storage and analytics. Reset releases owned preview URLs and pending work. Format limitations are reported rather than disguised as successful conversion.