Free online RTF to AAC converter

When a device or player accepts AAC audio but not RTF documents, converting the document creates a spoken version that can be played there. This is a text-to-speech conversion: the RTF formatting is read as text, then a voice is synthesized and encoded as AAC.

What the RTF format is

Rich Text Format (RTF) stores text with basic formatting such as fonts, emphasis, and paragraph structure. Word processors including Microsoft Word and LibreOffice Writer can create and open RTF files; they are also common as document attachments and as exports from older applications.

What the AAC format is

Advanced Audio Coding (AAC) is a lossy audio codec used for speech and music. It can deliver good sound at relatively low bitrates and is supported by many phones, media players, and streaming systems. AAC files are commonly stored in an .m4a container; some systems instead require an AAC bitstream with an .aac extension.

How to convert RTF to AAC

The source contains written content, not recorded sound. Conversion software must turn that content into speech before encoding the audio; document layout and most formatting do not carry over.

Online on 101convert.com

1. Upload the RTF file on the converter page. Several files can be added for batch conversion; the page shows the per-file size limit.
2. Choose the voice language and reading speed before converting.
3. Start the conversion, then download the resulting AAC file or files.

Offline with desktop software

On Windows, macOS, or Linux, use LibreOffice to extract plain text, eSpeak NG to synthesize speech, and FFmpeg to encode it. Install these programs, then run the commands in a terminal from the folder containing document.rtf:

libreoffice --headless --convert-to txt:Text --outdir . document.rtf
espeak-ng -v en-us -s 150 -f document.txt -w speech.wav
ffmpeg -i speech.wav -c:a aac -b:a 128k document.m4a

Change en-us to an installed eSpeak NG voice and adjust -s 150 to change the speaking rate. The final command creates AAC audio in an M4A container. If a device specifically requires an AAC bitstream, use ffmpeg -i speech.wav -c:a aac -b:a 128k -f adts document.aac instead.

Quality and compatibility

Speech intelligibility depends mainly on the selected voice, language, and reading speed; increasing the AAC bitrate cannot improve the synthesized pronunciation. Review the extracted document.txt before synthesis if the RTF contains tables, unusual symbols, or layout-dependent content, since plain-text extraction may not preserve their intended reading order.