MAXScanner engineering calculator
ADC Resolution Calculator — LSB Size, Quantization & Code
Calculate ideal ADC LSB size, code count, quantization uncertainty and saturated output code from bit depth, reference voltage and input voltage.
Last updated: September 16, 2026
Results
Levels 4,096
LSB 0.8056641 mV
Ideal code 2,048
Ideal quantization ±402.832 µV
Input is within the ideal reference range
Formula, example and assumptions
Levels=2^N; LSB≈Vref/2^N; code=floor(Vin/LSB), clamped to the available code range.
A 12-bit ADC with 3.3 V reference has an ideal LSB of about 0.806 mV.
- Ideal unipolar ADC transfer function with zero offset and gain error.
- Real ENOB, noise, INL, DNL, reference error and front-end settling reduce usable accuracy.
Frequently asked questions
Is resolution the same as accuracy?
No. Resolution is code granularity; accuracy also includes reference, offset, gain, linearity and noise errors.
What is quantization uncertainty?
For an ideal converter it is commonly described as about ±0.5 LSB.