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Local browser tool

Create mail merge documents locally.

Fill Word and Excel templates directly in the browser from a data table. Files are not uploaded.

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Templates

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Data table

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Sample files

These fictional files belong together: one data table, two Word templates, and one Excel template.

Sample data XLSX data table with three fictional companies. DownloadWord mail merge template DOCX template with placeholders and date/amount filters. DownloadWord invoice template Second DOCX template with filename placeholders. DownloadExcel template XLSX template with a header row and one template row. Download
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Help

Workflow

  • Upload an XLSX data table. The first sheet is read and the first row provides the column names.
  • Upload one or more DOCX or XLSX templates.
  • Review the detected columns and adjust the filename pattern for DOCX templates if needed.
  • Create a ZIP file with all results. Word templates create one document per data row.

Placeholders

  • Column names are normalized: spaces and special characters become underscores, percent signs become pct, uppercase letters become lowercase.
  • Example: RechnungsNr. becomes rechnungsnr_, Rabatt % becomes rabatt_pct, 1,3 GG becomes n1_3_gg.
  • Use placeholders like {{name}}, {{firma}}, or {{rechnungsnr_}} in DOCX and XLSX templates.
  • Empty or unknown placeholders will not be filled usefully. Check the column list after upload.

Filters

  • {{datum|fmt_date}} formats dates as 05/09/2026-style German dates.
  • {{leistungszeitraum|fmt_month}} formats dates as May 2026-style German month names.
  • {{betrag|fmt_dec}} formats numbers with German separators, for example 1.490,50.
  • {{iban|fmt_iban}} groups IBANs in blocks of four.

Filenames

  • The filename pattern may use simple placeholders such as {{firma}} or {{name}}.
  • If the template filename already contains placeholders, it is used as the default pattern.
  • Invalid filename characters such as / or : are replaced during export.

Excel templates

  • For XLSX templates, row 1 is the output header row.
  • Row 2 is the template row. Each cell may contain placeholders and filters.
  • The generated XLSX file then contains one row per data record.

PDF export

  • PDF export is optional and uses a locally vendored LibreOffice WASM runtime.
  • The first activation loads large local WASM files. No files are sent to a server.
  • Safari does not currently support this export reliably.

Local and safe

  • Processing runs in the browser. Templates, data, and results stay on your device.
  • Still treat Office templates from unknown sources carefully. Complex document formats can be intentionally malformed.
  • Macros are not needed by this tool. Prefer simple DOCX and XLSX files without active content.

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