Textera
The file format matters less than recording quality, but a few choices do help. Here is what to use for the most accurate transcription.
Lossless vs compressed
WAV and FLAC are lossless and preserve the most detail, which is ideal for difficult audio. MP3, M4A and AAC are compressed but transcribe very well at reasonable bitrates. Textera accepts all of them and 40+ formats in total.
Recommended recording settings
Aim for a clear mono or stereo recording at 16 kHz or higher. Keep the microphone close to the speaker and minimize background noise. These factors affect accuracy far more than the container format.
Large files are handled for you
If your file is over 25 MB, Textera compresses and splits it automatically, so you never have to convert or trim it manually before uploading.