Published by PitchChanger · Updated · How these guides are made
How to use this workflow
Find duration, channels and sample rate
Read these from a local media inspector or the source recorder. File size alone cannot reveal decoded storage.
Calculate one decoded buffer
Convert minutes to seconds, multiply by sample rate and channel count, then multiply by four. Divide by 1,048,576 for MiB.
Leave room for the actual operation
Keep the original, close unnecessary audio tabs and try a short representative excerpt. Use a desktop workflow if the complete source repeatedly fails.
Worked memory worksheet: 30 minutes of stereo audio
For 30 minutes at 48,000 Hz stereo, the frame count is 1,800 × 48,000 = 86,400,000. Two float32 channels hold 172,800,000 samples, or 691,200,000 bytes: about 659.18 MiB. The duration and rate in this example are assumed inputs, not a measured browser session.
A 128 kbps compressed copy of that same duration is about 28,800,000 bytes before container overhead. Its roughly 28.8 MB download size does not bound the decoded working set.
Swipe or scroll sideways to read all columns.
| 48 kHz stereo duration | One float32 buffer, bytes | MiB |
|---|---|---|
| 5 min | 115,200,000 | 109.86 |
| 30 min | 691,200,000 | 659.18 |
| 60 min | 1,382,400,000 | 1,318.36 |
Why the worksheet is a lower bound
An application may hold source bytes, decoded buffers, a rendered result, encoded output, waveform data and engine memory simultaneously. As an illustration, three 30-minute buffers of this size need about 1,977.54 MiB before those other allocations. Three is a scenario, not a measured multiplier for every PitchChanger tool.
Audio Converter uses an FFmpeg runtime with its own allocations; other tools use Web Audio buffers. Neither browser process memory nor device free RAM can be inferred precisely from this worksheet. A tab can fail below the device’s advertised RAM because of implementation and allocation limits.
Choose a smaller job without throwing away the original
The file picker’s 250,000,000-byte cap is an input check, not a duration or memory guarantee. A compact MP3 below the cap may still decode into a very large recording. The converter queues at most three files and processes them serially; that does not make arbitrary source lengths safe.
If you only need a short excerpt, create it in a capable local editor before loading the full source here. Keep channels and sample rate appropriate to the destination. Converting a long source in the same failing browser is not a reliable way to escape its memory limit.
Common questions
Does 250 MB mean any file below it will work?
No. Duration, channels, codec support, runtime allocations and available browser memory impose additional limits.
Is the float32 calculation the size of a saved 16-bit WAV?
No. It estimates a decoded float32 buffer. A PCM16 WAV uses two bytes per sample plus headers.