Barclays Software Testing Interview Questions & Answers

A technique that tests all pairs of input values instead of every combination, greatly reducing test cases while catching most defects.

Check access with valid, expired and missing tokens, role-based permissions, error codes and that sensitive data is never exposed.

Severity is impact on the system; priority is urgency of the fix. A crash in a rare report is high severity, low priority; a spelling mistake in the logo is low severity, high priority.

Break the work into modules and test cases, use past velocity or three-point estimation (optimistic, likely, pessimistic), add time for test data, environment issues, retesting and regression, and keep a risk buffer.

Testing services directly without the UI, checking status codes, responses, security and performance. It finds issues early and is faster than UI tests.

DELETE removes selected rows and can be rolled back; TRUNCATE quickly removes all rows and resets the table.

Valid transfer, insufficient balance, daily limit, wrong beneficiary, OTP failure, network drop mid-transaction, duplicate click and statement update.

Smoke tests run on every build for quick feedback; full regression runs less often, such as nightly or before release.

Valid card and PIN, wrong PIN, three failed attempts, amount above balance, amount above daily limit, invalid denomination, machine out of cash, network failure and receipt printing.

Verifying the application works across different hardware, software and settings combinations.

Code is built and tested automatically on each change; tests are quality gates that stop faulty builds from moving forward.

The hardware, software, data and configuration where testing happens, set up to mirror production as closely as practical.

A final document summarising what was tested, defects found and open, metrics, lessons learned and the recommendation for release.

A development model where each development phase has a matching testing phase, such as requirements with acceptance tests and design with integration tests.

Moves to the chosen floor, doors open and close, door sensor stops closing on obstruction, overload alarm, emergency button, behaviour in a power cut, max capacity and the floor display.

Shift left with early reviews, improve test design, automate regression, use better test data, add monitoring and learn from escaped defects.

Evaluating software to find defects and confirm it meets requirements. It reduces risk, protects users and saves the cost of fixing bugs after release.

Use mocks or stubs from the API contract such as Swagger, write test cases early and validate again when the real service is available.

Learning, test design and execution at the same time, without scripted cases — time-boxed sessions with a charter (e.g. 'explore checkout with coupons'), noting bugs and ideas. Great for finding edge cases.

A regular review where QA, development and product assess new bugs and decide severity, priority, owner and target release.

A bug is behaviour that deviates from agreed requirements; an enhancement is a new or improved capability beyond the current requirements.

INNER returns matching rows, LEFT keeps all left rows, RIGHT keeps all right rows and FULL keeps all rows from both tables.

Basic operations, division by zero, decimals, large numbers, order of operations, clear and backspace, repeated operations and memory keys.

Testing how a system moves between states based on events, for example an order going from placed to paid to shipped to delivered.

Valid login, invalid login, forgot password, locked account and session handling are the main scenarios to cover.

Re-testing existing features after a change. Automate stable, repetitive, high-value flows that run every release.

For a field accepting 1–100: valid class 1–100 (test 50), invalid below 1 (test −5), invalid above 100 (test 150). One value represents each class.

Rules such as NOT NULL, UNIQUE, PRIMARY KEY, FOREIGN KEY and CHECK that keep data valid and consistent.

Testing shows presence of defects, exhaustive testing is impossible, test early, defects cluster, the pesticide paradox, testing is context-dependent and absence-of-errors is a fallacy.

Re-check the requirement, reproduce with clear steps and evidence (screenshots, logs), discuss with the BA/PO and record the final decision.

Finding why a defect was introduced, such as unclear requirements or missed reviews, to prevent similar defects in future.

Black box tests behaviour without code knowledge; white box tests internal logic and paths; grey box uses partial knowledge of the internals.

The extent of requirements or code exercised by tests. Measure requirement coverage with a traceability matrix and code coverage with tools.

TDD writes unit tests before code to drive design; BDD describes behaviour in business language scenarios that become automated acceptance tests.

A model with many fast unit tests at the base, fewer API or integration tests in the middle and a small number of UI tests at the top.

The number of defects per size of software, for example defects per thousand lines of code or per module, used to compare quality.

A grid mapping requirements to test cases and defects, proving every requirement is tested.

State the problem, location and condition briefly, for example 'Checkout button disabled after applying a coupon on the cart page'.

An urgent patch released outside the normal schedule to fix a critical production defect, followed by regression testing and merge back to the main branch.

SDLC is the full software development life cycle; STLC is the testing life cycle: requirement analysis, test planning, test design, environment setup, execution and closure.

Alpha is done in-house by internal teams before release; beta is done by a limited group of real users in their own environment.

Test 17, 18, 19, 59, 60 and 61.

They let testers verify totals and counts per category, such as the number of orders per customer, and compare them with the UI or reports.

Defects found after release that testing should have caught; leakage % = defects in production / total defects x 100.

New → Assigned → Open → Fixed → Retest → Verified → Closed, with Reopened, Rejected, Deferred and Duplicate as side paths.

Measuring speed and stability: load (expected users), stress (beyond limits), spike (sudden surge), endurance (long duration) and scalability testing.

A scenario is a high-level thing to test (user logs in); test cases are the detailed steps and data that verify it.

Talk to developers and users, explore the product, review similar systems, create notes and mind maps, confirm assumptions and write test cases as you learn.

The inputs used in tests. Prepare using valid, invalid and boundary values from production-like but masked data, spreadsheets or generators.

The observation that a small number of modules contain most defects, so testing should focus on those areas.

Sprint planning (estimate test effort), daily stand-up (status and blockers), sprint review (demo) and retrospective (improve). Testers clarify acceptance criteria early and test within the sprint.

Checking that people with disabilities can use the product, using screen readers, keyboard navigation, colour contrast and WCAG guidelines.

Status code, response body and schema, headers, response time, error messages for invalid input, authentication (401/403) and that data is saved in the database.

Re-check environment, data, browser and steps; check the logs; try the reporter's setup; add video and console logs; mark it 'cannot reproduce' only after discussing with the developer, and keep monitoring.

Positive cases use valid inputs to confirm expected behaviour; negative cases use invalid inputs to confirm the system handles errors gracefully.

Assess impact and risk, discuss with product and dev, decide to fix, defer with a workaround or delay release, and document the decision.