Audio Bitrate Calculator

Calculate audio bitrate from file size and duration.

File Size

Duration

Hours

Minutes

Seconds

Understanding Audio Bitrate

Audio bitrate determines the quality and file size of digital audio. It measures how many bits of data are processed per second, typically expressed in kilobits per second (kbps). Higher bitrates generally mean better audio quality but larger file sizes.

Audio Bitrate Quality Standards

Quality Level	Bitrate Range	Use Case	File Size (1 hour)
Low Quality	32-64 kbps	Voice calls, voice memos	14-28 MB
Acceptable	96 kbps	Podcasts, audiobooks, speech	42 MB
Good	128 kbps	Standard music streaming, FM radio quality	56 MB
High Quality	192 kbps	Music downloads, CD-like quality	84 MB
Very High Quality	256 kbps	Premium music streaming	112 MB
Studio Quality	320 kbps	Professional audio, archival	140 MB
Lossless	700-1,400 kbps	FLAC, ALAC, uncompressed audio	300-600 MB

Common Audio Formats and Bitrates

Lossy Formats

MP3: 128-320 kbps (most compatible)
AAC: 96-256 kbps (better quality than MP3)
OGG Vorbis: 96-256 kbps (open source)
Opus: 64-192 kbps (modern, efficient)

Lossless Formats

FLAC: 700-1,000 kbps (free, open)
ALAC: 700-1,000 kbps (Apple)
WAV: 1,411 kbps (uncompressed)
AIFF: 1,411 kbps (uncompressed)

Bitrate Calculation Formula

Bitrate (kbps) = (File Size in KB × 8) / Duration in seconds

Example: A 5 MB file that's 3 minutes (180 seconds) long:
5,120 KB × 8 / 180 = 227 kbps

Streaming Service Bitrates

Service	Standard	High Quality	Lossless
Spotify	96 kbps	160 kbps	320 kbps (Premium)
Apple Music	128 kbps	256 kbps (AAC)	ALAC Lossless
YouTube Music	128 kbps	256 kbps	-
Amazon Music	128 kbps	256 kbps	HD Lossless
Tidal	160 kbps	320 kbps	FLAC (HiFi)

Factors Affecting Audio Bitrate Choice

Content Type: Music needs higher bitrates than speech/podcasts
Playback Device: High-end audio systems benefit from higher bitrates
Storage Limitations: Mobile devices may require compressed formats
Bandwidth: Streaming requires balance between quality and data usage
Codec Efficiency: Modern codecs (AAC, Opus) sound better at lower bitrates

Podcast Production Guidelines

For podcast production, consider these bitrate recommendations:

Solo voice: 64 kbps mono is sufficient
Interview/multiple voices: 96 kbps mono or 128 kbps stereo
Music content: 128-192 kbps stereo
High production: 192-256 kbps stereo

Pro Tip: For most music listening, 192 kbps AAC or 256 kbps MP3 provides excellent quality that's indistinguishable from lossless for most people on most equipment. Use higher bitrates only if you have high-end audio equipment and trained ears.

Sample Rate and Bit Depth

In addition to bitrate, audio quality is affected by:

Sample Rate: 44.1 kHz (CD quality), 48 kHz (video), 96+ kHz (studio)
Bit Depth: 16-bit (standard), 24-bit (professional), 32-bit (mastering)
Channels: Mono (1), Stereo (2), Surround (5.1, 7.1)

Variable vs Constant Bitrate

CBR (Constant Bitrate)

Pros: Predictable file size, better compatibility, streaming-friendly

Cons: Less efficient, may waste bits on simple passages

VBR (Variable Bitrate)

Pros: Better quality per file size, efficient compression

Cons: Unpredictable size, may have compatibility issues

Quick Reference

Common Bitrates:

64 kbps: Voice only
96 kbps: Podcasts
128 kbps: Music (min)
192 kbps: High quality
256 kbps: Premium
320 kbps: Maximum MP3

File Size Guide

1 Hour of Audio:

64 kbps: 28 MB
128 kbps: 56 MB
192 kbps: 84 MB
256 kbps: 112 MB
320 kbps: 140 MB

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