Why Bulk Conversion Matters

Organisations that have accumulated large archives of Tamil documents — government departments, publishers, newspapers, educational institutions, and NGOs — often need to convert hundreds or thousands of files from legacy encoding to Unicode. Doing this one file at a time is impractical. Bulk conversion tools make this feasible.

FontConvertor.in's Bulk Converter lets you upload multiple files at once and convert all of them in a single operation — no software to install, no technical knowledge required, completely free.

Supported File Formats

The bulk converter accepts the following file formats:

• .txt — Plain text files
• .docx — Microsoft Word documents (2007 and later)
• .xlsx / .xls — Microsoft Excel spreadsheets
• .html / .htm — Web pages
• .rtf — Rich Text Format
• .csv — Comma-separated values
• .tsv — Tab-separated values

Note: PDF files are not supported for bulk conversion because PDFs require OCR or text extraction as a separate step. Convert PDFs using the method described in our Tamil PDF conversion guide, then upload the extracted text files for bulk processing.

Step-by-Step: Bulk Convert Tamil Files

1. Go to FontConvertor.in/bulk-converter.
2. Select your source font — choose the legacy font encoding your files use (Bamini, SenTamil, TSCII, Vanavil, etc.).
3. Select Unicode as the target font.
4. Upload your files — click the upload area or drag and drop multiple files at once. You can upload up to the supported limit in one batch.
5. Click Convert All — all files are processed simultaneously. Each file shows its status: converting → done.
6. Download the results — download each file individually or click Download All to get all converted files at once as a ZIP.

Tips for Best Results

Sort Your Files by Encoding First

The bulk converter applies the same source font to all files in a batch. If your archive has files in different encodings (some Bamini, some TSCII, etc.), separate them into folders by encoding and process each folder separately.

Test with a Sample First

Before processing hundreds of files, upload 3–5 representative samples from your archive and verify the output quality. This catches any encoding mismatch before it affects the entire batch.

Handle Mixed-Language Files Carefully

Files that mix Tamil and English text will have the English portions affected by the conversion. If your files contain significant English text, consider extracting the Tamil sections first, or manually review the output of mixed files.

For Excel Files

When converting Excel files, the bulk converter extracts text from all cells in all sheets. The output is a plain text file with values separated by tabs. If you need the data back in spreadsheet format, paste the converted text into a new Excel file.

Batch Converting a Document Archive

For a large archive conversion project (hundreds of files), here is the recommended workflow:

1. Sort by format: Separate .docx, .txt, and other formats into different folders.
2. Sort by encoding: If you know which files use which encoding, group them accordingly.
3. Process in batches of 20–30 files for reliable results.
4. Verify a random sample from each batch to confirm quality.
5. Store both versions — keep the original legacy files as backup and the converted Unicode files as the working copies.
6. Name files clearly — add "_unicode" to converted filenames to distinguish them from originals.

Using the API for Automated Bulk Conversion

If you're a developer or technical user with a very large archive (thousands of files), the manual bulk converter may not be the most efficient approach. The FontConvertor.in REST API lets you automate the conversion programmatically:

• Write a script that reads each file, posts the text to the API, and saves the returned Unicode output.
• Process files in parallel for maximum speed.
• Integrate the conversion into your existing document management workflow.

The API is free during beta — get your API key on the developers page.

Common Questions

Is there a file size limit? Each file should be under 10 MB for best performance. Very large files may be split into sections first.

Is my content private? Yes — all conversion happens in your browser. Your files are never uploaded to any server. Processing is entirely local.

Can I convert back from Unicode to legacy fonts? Yes — select your target legacy font in the target dropdown and Unicode as the source. The same bulk process works in reverse.

Start bulk converting your Tamil documents — free, no signup, no software needed.