Podcast Audio Compressor

Podcast file compression vs dynamic range compression

This tool changes delivery format, bitrate, sample rate, and channel count to control bytes. A studio compressor changes the difference between louder and quieter moments. Loudness measurement and a LUFS target are also separate. No preset here claims to master an episode, normalize loudness, reduce noise, or satisfy a changing platform rule.

Use the tool after editorial and mastering decisions when you need a practical publishing copy. The CBR vs VBR guide explains bitrate modes, while What Is an Audio Compressor? covers dynamics.

Mono and stereo podcast exports

A solo voice recorded centrally can often use mono without losing intended placement. Interviews may also be mono after mixing, but a raw two-track interview can keep guests or microphones separated. Narrative shows, music beds, field ambience, and stereo transitions normally justify two channels because the spatial relationship is part of the program.

The presets make those choices visible instead of hiding them behind a quality label. Listen after downmixing. Keep the production session or master even when the delivery version is mono, because later edits may need separated tracks.

Bitrate choices for speech and music

Solo speech begins at a compact mono setting. Interviews retain more total data when stereo is useful. Narrative-with-music and music-heavy presets allocate progressively more bitrate because sibilants, ambience, transients, and layered music expose artifacts sooner than steady close-mic speech. A trailer balances mixed content with a short duration.

The numbers are starting points, not quality scores. An encoder, codec, mode, and source all affect the listening result. Re-encoding a low-quality download at 192 kbps does not recover the detail that the earlier file discarded.

Estimating episode and archive size

Before export, episode bytes are estimated from measured duration and selected bitrate. The planner then multiplies that estimate across 4, 8, or 12 episodes per month, or your own publishing frequency and retention period. After export, the planner switches to the actual Blob size so projections are grounded in the file you created.

Listener delivery appears only when you enter downloads per episode. It is simple byte multiplication, not a hosting invoice: CDN caches, partial requests, retries, analytics definitions, free tiers, and protocol overhead are outside the model. Use Audio Storage Calculator for capacity-first planning.

MP3 vs AAC for distribution

MP3 is a conservative compatibility option. AAC in an M4A container can be efficient for modern playback paths, but support must be checked in the actual host, feed, browser, and app chain. The tool only exposes encoders present in its audited ffmpeg.wasm build and does not claim universal acceptance by a named platform.

Browser preview support can also differ from encoding support. If an AAC result does not play inline, download and test it in the intended player or create MP3 instead. Codec choice is distinct from CBR/VBR mode.

Why loudness targets are a separate issue

Bitrate does not describe perceived loudness. LUFS measurements, true-peak limits, dynamics, and program balance require audio analysis and processing that this publishing-size tool does not perform. A smaller file can be louder, quieter, or unchanged depending on the source and encoder; the page makes no automatic loudness claim.

Finish editorial mixing and loudness work in an appropriate audio editor, keep the master, and use this page for the final size-oriented copy. This separation prevents a target MB field from being mistaken for mastering.

Practical podcast export examples

A strict target size reserves a safety margin, but only the generated file’s measured bytes are an actual result.