Learntotest
AI-guided test casesfor the code you paste— predict first,reveal later.
How it worksScroll
About Testing123
Created in 2026, Testing123 turns any component you paste into the test cases you should write providing the reasoning behind each one, before a single line of test code is revealed.
How the guidance worksHow it works
PasteAnything
Drop in a component, a hook, or a plain function. Testing123 reads the shape of the code and works out what its behaviour actually is.
Know more- Languages
- TS / JS
- Frameworks
- React, Vue, Svelte
- Paste limit
- None
PredictFirst
Before a single assertion is revealed, you commit to what you think should be tested. The gap between your and ours is the lesson.
Know more- Cases per component
- 6 – 20
- Reveal
- On your call
- Scoring
- Per case
RevealOn Demand
Each case comes with the reasoning behind it. Code last, never first.
Know more- Explanations
- Every case
- Concepts taught
- +60
- Code shown
- Last
SwitchLibraries
The same predicted cases work for whichever framework you use. Same knowledge, different syntax.
Know more- Runners
- Jest, Vitest
- DOM
- RTL
- E2E
- Playwright
Our stack
Vitest
VitestJest
JestTesting Library
Testing LibraryPlaywright*
Playwright*Cypress*
Cypress*Vitest
VitestJest
JestTesting Library
Testing LibraryPlaywright*
Playwright*Cypress*
Cypress*Vitest
VitestJest
JestTesting Library
Testing LibraryPlaywright*
Playwright*Cypress*
Cypress*Vitest
VitestVitestJestTesting LibraryPlaywright*Cypress*
Switch syntax across multiple testing frameworks.
The team
