◆ Sparround

Test design techniques

Black-box test design techniques minimise the number of tests while maximising coverage:

  • Equivalence Partitioning (EP) — split inputs into classes with identical behaviour and test 1 value per class
  • Boundary Value Analysis (BVA) — test the boundaries and both sides (bugs live at the edges)
  • Decision Table — cover all condition combinations of complex business rules in a table
  • State Transition — test transitions between system states (e.g. order statuses)
  • Pairwise — cover pair combinations for multi-parameter cases

Practical tasks are common in interviews: "How would you test a field accepting 1-100?" Always answer with EP + BVA + invalid inputs (empty, letters, negative, decimal, very long, special characters, SQL/XSS attempts).