LLD Interview Guide

One method. Every problem.

Low-level design interview preparation

Learn how to reach the design—not just what the final design looks like.

Every lesson follows the same five steps: clarify requirements, find entities, derive classes, write Java code, and handle extensions.

Start with the method

LLD Interview Framework

The question groups, order, and timing to reuse in every interview.

10 minute lesson

Complete problem walkthroughs

Java · diagrams · simulations
01

Elevator System

Derive the requirements, choose the objects, write the Java design, and test it with a working simulation.

Intermediate35 min
02

Tic-Tac-Toe

Turn interview answers into game rules, complete Java classes, and a move-by-move working simulation.

Beginner30 min