Build a Simple HTML Calculator | Frontend Coding Challenge | Vanilla JavaScript | Machine Coding Round
@Yomesh Gupta

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In this question, you need to build a simple HTML calculator that performs the following basic operations:

  1. Addition
  2. Subtraction
  3. Division
  4. Multiplication
  5. Modulo
  6. Bracket Computation
  7. Clear
  8. Decimal Operations



HTML Calculator Mockup

Styling Information


  • Body Background: #fdfdfd
  • Calculator Background: #2f3640
  • Numbers: #718093
  • Operators: #fbc531

Box Shadow

rgba(0, 0, 0, 0.35) 0px 5px 15px;

Points to remember

  1. It is imperative that candidate must write clean, modular, and easy to follow code.
  2. This is a beginner-friendly exercise where the candidate would be judged on code structure, attention to detail, and execution speed. Use the timer provided to measure how fast you completed the exercise.
  3. Take the mockup as frame of reference and use your creative sense to add more functionalities, enhance UI, and make it more feature rich.