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Analog to Digital Calculator

Free analog-to-digital calculator — bit depth, quantization levels, sample rate, bit rate, and Nyquist check, with an animated sampling diagram.

analog (continuous) digital (8 levels) 4 samples/cycle

Bit depth (resolution)

Sample rate (Hz)

Highest signal freq (Hz)

Channels

Duration (seconds, optional)

Bit depth sets how many levels the analog signal is rounded to; sample rate sets how often it is measured. Together they turn a continuous (analog) wave into numbers (digital).

⚠️ Please enter a whole bit depth between 1 and 32.

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Everyday Uses

Audio recording

See why CD is 16-bit/44.1 kHz and why higher sample rates and bit depths sound cleaner — and cost more storage.

File size planning

Estimate the uncompressed size of audio from bit depth, sample rate, channels, and duration before you record.

Learning DSP

Sampling, quantization, and the Nyquist theorem made visible — the animated wave becomes digital steps as you watch.

Electronics projects

Choosing an ADC for an Arduino or sensor? Check resolution, sample rate, and the Nyquist limit for your signal.

What a sensor can actually resolve

A 10-bit converter splits its range into 1,024 steps and a 12-bit one into 4,096. That decides the smallest temperature or voltage change your project can genuinely detect.

Why CD audio stops at 44.1 kHz

Nyquist requires sampling above twice the highest frequency present. Human hearing tops out near 20 kHz, so 44.1 kHz clears it with room for the anti-aliasing filter.

Frequently Asked Questions

What is the difference between analog and digital?

Analog signals are continuous — they can take any value smoothly, like the groove on a vinyl record, a dimmer switch, or a real sound wave. Digital signals are discrete — the value is measured at regular moments (sampling) and rounded to a fixed set of levels (quantization), producing numbers a computer can store. The animated diagram shows a smooth analog wave being turned into a red staircase of digital steps.

What is bit depth and how many levels does it give?

Bit depth is how many bits represent each sample, and it sets the number of quantization levels = 2 to the power of the bit depth. 8-bit gives 256 levels, 16-bit (CD audio) gives 65,536 levels, 24-bit gives over 16 million. More bits mean finer steps, so the digital version rounds the analog signal less and adds less "quantization noise".

What is the Nyquist rate?

The Nyquist theorem says you must sample at least twice the highest frequency in a signal to capture it correctly: sample rate ≥ 2 × highest frequency. Human hearing tops out near 20 kHz, so CD audio samples at 44,100 Hz (just above 2 × 20,000). Sampling too slowly causes aliasing, where high frequencies masquerade as false lower ones — this calculator warns you when your rate is too low.

How do you calculate the bit rate and file size?

Bit rate = sample rate × bit depth × channels. CD audio is 44,100 × 16 × 2 = 1,411,200 bit/s (1,411 kbit/s). Uncompressed file size = bit rate × duration in seconds ÷ 8 for bytes. A 3-minute CD-quality track is about 44,100 × 16 × 2 × 180 ÷ 8 ≈ 31.75 MB — which is why compression formats like MP3 exist.