Hex NOR Calculator

Calculates the bitwise NOR (NOT of OR) of two hexadecimal values: the shorter value is left-padded with zero digits to match the longer one's width, then NOR is applied across every nibble-aligned bit position. A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-26

Overview

Introduction

NOR is a "universal" logic gate: every other logic gate (AND, OR, NOT, XOR, and the rest) can be built entirely out of NOR gates, which is part of why it shows up so often in digital logic design.

This tool computes the bitwise NOR of two hexadecimal values, letting you see exactly how the gate behaves across real hex-encoded data rather than a single pair of bits.

What Is Hex NOR Calculator?

A calculator for the bitwise NOR (NOT-OR) of two hex values: it ORs the two values together bit by bit, then inverts every bit of that result.

Because NOR takes two operands that might not be the same length, this tool automatically left-pads the shorter one with zero digits so both values line up bit-for-bit before combining them.

How Hex NOR Calculator Works

Both Value A and Value B are validated as hex strings, then the shorter is left-padded with leading zero digits to match the longer value's digit count.

The padded values are combined bit-by-bit with OR, and the OR result is then complemented (every bit flipped) across that same width to produce the final NOR output.

When To Use Hex NOR Calculator

Use it while studying digital logic to see concretely how NOR behaves across multi-bit hex values, not just a textbook single-bit truth table.

It's also useful when reverse-engineering or documenting hardware/protocol logic that's specified in terms of NOR gates operating on byte- or word-sized values.

Often used alongside Hex XNOR Calculator and Hex NOT Calculator.

Features

Advantages

  • Automatically handles operands of different lengths by zero-padding, so you don't have to align widths by hand first.
  • Works on arbitrarily long hex values via BigInt, not limited to a fixed 8/16/32/64-bit width.
  • Instant, deterministic, fully client-side.

Limitations

  • Zero-padding the shorter operand assumes you want it treated as a smaller number within a larger field; if your protocol expects different alignment (e.g. right-padding), pad the value manually before pasting it in.
  • Doesn't validate that either operand represents a specific fixed-width type (byte, word, etc.); width is inferred purely from digit count after padding.

Examples

NOR of two complementary nibble patterns

Input

A: F0, B: 0F

Output

00

F0 (11110000) OR 0F (00001111) = FF (11111111); NOT of FF is 00. Every bit position has at least one 1, so NOR is all zeros.

NOR of two mixed bit patterns

Input

A: A5, B: 3C

Output

42

A5 (10100101) OR 3C (00111100) = BD (10111101); NOT of BD is 42 (01000010).

Best Practices & Notes

Best Practices

  • Confirm both values are the width you intend before relying on the auto-padding, especially if a short value like "1" should really mean "0001" in your context.
  • Use the NOR result together with the Hex NOT Calculator to double-check the intermediate OR step if a result looks surprising.

Developer Notes

Implemented with JavaScript BigInt: after zero-padding both operands to the same digit width, it computes (mask XOR (a OR b)) where mask is all-1s across that width, which is equivalent to NOT(A OR B) without JavaScript's native 32-bit-limited bitwise operators getting in the way.

Hex NOR Calculator Use Cases

  • Studying or teaching the NOR logic gate using concrete multi-bit hex examples
  • Reverse-engineering hardware or protocol logic specified in terms of NOR operations
  • Cross-checking a manually-computed NOR result

Common Mistakes

  • Assuming NOR and NAND are interchangeable; NOR is NOT(A OR B), NAND is NOT(A AND B), and they behave differently on the same inputs.
  • Forgetting that a short operand gets zero-padded on the left, which can change the intended meaning if you actually wanted it right-aligned.

Tips

  • Pad both values to the same length yourself first if you want to be certain about alignment rather than relying on automatic left-padding.
  • Try the Hex XNOR Calculator to see how a closely related gate (NOT of XOR rather than NOT of OR) behaves on the same inputs.

References

Frequently Asked Questions