Best Audio Formats for Transcription
File format matters less than clear speech, but it still affects quality, upload size and compatibility. Use the original file whenever possible.
Choose the best source you already have
Clear speech, microphone distance, room echo and overlapping voices matter more than a file extension. Keep a complete original recording when possible. Changing an extension does not convert a file, and converting compressed audio to a larger format cannot restore detail already lost. AudText accepts supported files up to 100 MB.
WAV: detail with larger uploads
WAV is commonly used for uncompressed recordings. An original, clear WAV can preserve speech detail, but its larger size may reach the upload limit sooner than a compressed recording. Use it when your recorder provides it and the file fits the upload limit.
FLAC: a lossless source
FLAC uses lossless compression, preserving the recorded audio while often taking less space than an uncompressed WAV. It can be useful when keeping a high-quality source matters. Check speech and recording levels first; a lossless file still preserves noise and clipping.
MP3: practical for sharing recordings
An original MP3 with clear speech is suitable for many interviews, voice recordings and podcasts. Very low-quality compression or repeated re-encoding can reduce the speech detail available for recognition. Use the MP3 directly when it is the best source you have.
M4A: upload the original voice memo
Phones and voice recording apps commonly save M4A files. Select the actual recording rather than a sharing link, and upload it directly instead of converting it to MP3. Check that the file plays, is complete and is no larger than 100 MB. An accepted .m4a extension alone does not guarantee that every recording can be decoded.
WebM and other supported sources
Browser recordings and meeting tools can produce WebM files. AudText also accepts AAC, OGG, OGA, OPUS, WMA and MPGA audio extensions, along with supported video formats. Keep the original source and select its spoken language before processing; a corrupt or incomplete file may still fail.
Choose the export after transcription
Source format and export format solve different tasks. Review the transcript with word playback, then choose TXT, DOCX or PDF for text and documents, JSON for available structured timing data, or SRT and VTT for captions. Plain text edits do not update the generated captions or original word timing.