Bit Depth Calculator
Calculate the dynamic range of any bit depth using DR = 6.02n + 1.76 dB. Output: dynamic range, quantization levels (2ⁿ), step size, data rate, and PCM file-size estimates. Supports 1 to 64-bit (1-bit DSD through 32-bit float).
Input
Result
Bit Depth Comparison
| Bit Depth | Dynamic Range | Levels (2ⁿ) | 1 min Stereo 44.1k | Typical Use |
|---|---|---|---|---|
| 1-bit | 7.78 dB | 2 | ~0.66 MB | DSD / Sigma-delta modulation |
| 4-bit | 25.84 dB | 16 | ~2.65 MB | Ancient sample-based games |
| 8-bit | 49.92 dB | 256 | ~5.29 MB | Lo-fi audio, telephone PCM (µ-law/A-law) |
| 12-bit | 74.00 dB | 4,096 | ~7.94 MB | AM radio, low-end ADPCM |
| 16-bit | 98.08 dB | 65,536 | ~10.58 MB | CD Audio, consumer download standard |
| 20-bit | 122.16 dB | 1,048,576 | ~13.23 MB | Pro audio, DAT, some older studio gear |
| 24-bit | 146.24 dB | 16,777,216 | ~15.87 MB | Pro audio, hi-res downloads, Blu-ray |
| 32-bit int | 194.40 dB | ~4.29 × 10⁹ | ~21.17 MB | Float-buffer intermediates, rare delivery |
| 32-bit float | ~1500 dB | 2³² values | ~21.17 MB | Production / mixing / mastering DAWs |
About Bit Depth & Dynamic Range
Bit depth (n) determines how many discrete amplitude levels each sample can take: levels = 2ⁿ. With more bits, you can represent quieter sounds without losing them to quantization noise — the rounding error introduced when a continuous audio waveform is mapped onto a finite set of integer values during analog-to-digital conversion (ADC). The theoretical signal-to-noise ratio of an ideal n-bit ADC is DR = 6.02n + 1.76 dB (Bennett's formula, assuming uniform quantization noise). This same figure is also called the theoretical SNR or SQNR (signal-to-quantization-noise ratio) in digital signal processing texts. As a dynamic range calculator, this tool applies that formula instantly for any bit depth from 1 to 64, alongside quantization level counts and audio file size estimates.
Why 6.02 per bit?
Each bit doubles the number of representable levels (2× factor in amplitude resolution). Amplitude doubling = 20 × log₁₀(2) = 6.0206 dB. The extra 1.76 dB comes from the assumption that quantization noise is uniformly distributed (mathematically: 10 × log₁₀(3/2)) — a refinement Walter Bennett published in 1948. The formula is the asymptotic best case; real ADCs are slightly noisier.
Why 16-bit for CDs?
16-bit gives 98 dB dynamic range — broadly matching the dynamic range of human hearing (about 120 dB total, but ~90 dB for usable music without pain). It also fits efficiently into computer memory (2 bytes per sample). The CD format committee in 1980 picked 16-bit as the sweet spot between fidelity, file size, and the cost of digital electronics at the time.
Why 24-bit for production?
24-bit gives 146 dB dynamic range — far more than any speaker, microphone, or human ear can use directly. The point isn't delivery; it's headroom during processing. When you cut/boost EQ, add compression, mix multiple tracks, etc., quantization errors can accumulate in a process known as requantization noise. The extra 48 dB headroom of 24-bit vs 16-bit (8 bits × 6.02) lets producers perform many operations without audible degradation. The final master can then be dithered down to 16-bit for delivery. For the complementary question of how sample rate affects frequency bandwidth and file size, see the sample rate converter.
32-bit float — the production format
32-bit float audio uses IEEE 754 floating-point representation: ~1500 dB effective dynamic range with virtually no clipping (a value of 2 = +6 dB above 0 dBFS — you can recover from "over" peaks). Most modern DAWs (Logic, Pro Tools, Reaper, Ableton) operate internally in 32-bit float. Delivery formats stay at 16-bit or 24-bit since the float advantages don't apply to passive listening. Some newer recording devices (like the Zoom F-series and Sound Devices MixPre) offer dual-converter 32-bit float recording, allowing you to capture extremely dynamic events — film explosions, live concerts — with guaranteed no-clip performance. You can verify how your bit depth choices translate to decibel headroom margins using the dB addition calculator alongside this tool.
Worked example: calculate 16-bit dynamic range and file size by hand
Given n = 16 bits, here is how to work out every output this tool produces:
- Dynamic range: DR = 6.02 × 16 + 1.76 = 96.32 + 1.76 = 98.08 dB
- Quantization levels: 216 = 65,536 distinct amplitude values
- Step size: 1 ÷ 65,536 ≈ 0.00153 % of full scale (≈ −96.3 dBFS per step)
- PCM data rate (stereo, 44,100 Hz): 44,100 × (16 ÷ 8) × 2 = 44,100 × 2 × 2 = 176,400 bytes/s ≈ 1,411 kbps
- Uncompressed file size for 60 seconds: 176,400 × 60 = 10,584,000 bytes ≈ 10.09 MiB (10.58 MB)
Common reference points: 16-bit / 44.1 kHz (CD) = 98.08 dB DR, 1,411 kbps; 24-bit / 48 kHz (broadcast/production standard) = 146.24 dB DR, 2,304 kbps. The same arithmetic applies at any bit depth — just substitute n. For the complementary sample-rate side of the equation (Nyquist bandwidth and aliasing), use the sample rate converter.