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JavaScript Quizzes
Test your knowledge of JavaScript the language itself.
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Sort: most accepted
1. Promise order
JavaScript
Promise
easy
4959 accepted
2. Promise executor
JavaScript
Promise
easy
4466 accepted
3. Promise then callbacks
JavaScript
Promise
easy
3215 accepted
5. scope
JavaScript
easy
2829 accepted
4. Promise then callbacks II
JavaScript
Promise
easy
2305 accepted
7. Increment Operator
JavaScript
easy
2292 accepted
8. Implicit Coercion I
JavaScript
easy
1753 accepted
6. Arrow Function
JavaScript
medium
1529 accepted
10. Equal
JavaScript
easy
1400 accepted
93. string
JavaScript
easy
1129 accepted
9. null and undefined
JavaScript
medium
1121 accepted
69. undefined
JavaScript
easy
1044 accepted
97. `this` V
JavaScript
easy
1015 accepted
12. arguments
JavaScript
medium
1006 accepted
13. Operator precedence
JavaScript
easy
994 accepted
89. let
JavaScript
easy
983 accepted
27. Hoisting I
JavaScript
easy
972 accepted
28. Hoisting II
JavaScript
easy
860 accepted
70. function
JavaScript
easy
851 accepted
86. setTimeout III
JavaScript
easy
841 accepted
11. Implicit Coercion II
JavaScript
easy
787 accepted
29. Hoisting III
JavaScript
easy
783 accepted
39. var
JavaScript
easy
755 accepted
17. reduce
JavaScript
medium
747 accepted
19. `this`
JavaScript
easy
738 accepted
23. Promise.all()
JavaScript
easy
683 accepted
18. Promise executor II
JavaScript
easy
678 accepted
96. comparison
JavaScript
easy
669 accepted
41. `this` III
JavaScript
easy
667 accepted
79. Equal III
JavaScript
easy
647 accepted
99. closure
JavaScript
easy
643 accepted
61. onClick
JavaScript
easy
638 accepted
45. Hoisting VI
JavaScript
easy
616 accepted
67. if
JavaScript
easy
608 accepted
94. emoji
JavaScript
easy
602 accepted
54. setTimeout(0ms)
JavaScript
easy
601 accepted
15. instanceOf
JavaScript
easy
599 accepted
100. `var` vs `let`
JavaScript
easy
595 accepted
14. Addition vs Unary Plus
JavaScript
easy
583 accepted
38. Hoisting IV
JavaScript
easy
580 accepted
37. push unshift
JavaScript
easy
577 accepted
63. in
JavaScript
easy
570 accepted
120. try..catch..finally
JavaScript
easy
569 accepted
33. `this` II
JavaScript
easy
567 accepted
117. `this` VII
JavaScript
easy
562 accepted
105. typeof
JavaScript
easy
557 accepted
47. Promise Order II
JavaScript
easy
557 accepted
111. falsy
JavaScript
easy
551 accepted
76. const
JavaScript
hard?
545 accepted
44. Function call
JavaScript
easy
542 accepted
81. setTimeout II
JavaScript
easy
540 accepted
22. min max
JavaScript
easy
527 accepted
16. parseInt
JavaScript
easy
527 accepted
113. push
JavaScript
medium
526 accepted
46. Implicit Coercion IV
JavaScript
easy
526 accepted
65. Function name
JavaScript
easy
520 accepted
124. comma 2
JavaScript
easy
511 accepted
91. largest Array index
JavaScript
easy
508 accepted
72. Array length
JavaScript
easy
497 accepted
107. `this` VI
JavaScript
easy
495 accepted
68. if II
JavaScript
medium
488 accepted
49. `this` IV
JavaScript
easy
488 accepted
92. NaN
JavaScript
easy
484 accepted
95. number format
JavaScript
easy
468 accepted
88. try...catch
JavaScript
easy
467 accepted
21. Array I
JavaScript
medium
460 accepted
32. Hoisting IIII
JavaScript
easy
459 accepted
50. async await
JavaScript
easy
458 accepted
36. Promise.prototype.finally()
JavaScript
easy
448 accepted
24. Equality & Sameness
JavaScript
easy
439 accepted
20. name for Function expression
JavaScript
medium
438 accepted
114. constructor
JavaScript
easy
432 accepted
48. Prototype
JavaScript
easy
431 accepted
53. Prototype 2
JavaScript
easy
430 accepted
115. parseInt II
JavaScript
easy
427 accepted
84. Array.prototype.sort()
JavaScript
medium
426 accepted
74. Typed Array length
JavaScript
easy
421 accepted
26. true or false
JavaScript
easy
417 accepted
116. strict
JavaScript
easy
413 accepted
103. Promise Order III
JavaScript
easy
406 accepted
109. isNaN()
JavaScript
easy
394 accepted
106. Promise.all() II
JavaScript
easy
394 accepted
123. return in Generator 2
JavaScript
easy
383 accepted
34. precedence
JavaScript
easy
381 accepted
87. instanceOf 2
JavaScript
easy
368 accepted
42. Hoisting V
JavaScript
medium
362 accepted
122. Iterable
JavaScript
easy
361 accepted
98. Promise executor IV
Promise
easy
361 accepted
102. Arrow Function II
JavaScript
easy
351 accepted
108. property key
JavaScript
easy
337 accepted
60. postMessage
JavaScript
easy
337 accepted
64. reference type
JavaScript
easy
335 accepted
25. zero
JavaScript
easy
332 accepted
30. Equal II
JavaScript
easy
331 accepted
66. comma
JavaScript
easy
318 accepted
101. Equal IV
JavaScript
easy
317 accepted
104. Inheritance
JavaScript
easy
311 accepted
59. override setter
JavaScript
easy
311 accepted
112. Symbol
JavaScript
easy
301 accepted
31. Math
JavaScript
easy
294 accepted
43. JSON.stringify()
JavaScript
medium
292 accepted
40. RegExp.prototype.test
JavaScript
easy
285 accepted
62. MessageChannel
JavaScript
easy
280 accepted
57. non-writable
JavaScript
easy
277 accepted
83. Plus Plus
JavaScript
easy
276 accepted
77. parseInt 2
JavaScript
easy
259 accepted
52. requestAnimationFrame
JavaScript
easy
259 accepted
118. structuredClone()
JavaScript
easy
249 accepted
73. window name
JavaScript
medium
243 accepted
90. array keys
JavaScript
medium
235 accepted
55. sparse array
JavaScript
medium
235 accepted
71. two-way generator
JavaScript
easy
230 accepted
35. Implicit Coercion III
JavaScript
easy
225 accepted
110. yield
JavaScript
easy
219 accepted
58. inherit getter setter
JavaScript
easy
218 accepted
56. to primitive
JavaScript
easy
211 accepted
75. meaningless calculation
JavaScript
easy
207 accepted
51. method
JavaScript
medium
198 accepted
85. String.raw()
JavaScript
medium
196 accepted
126. Object.keys()
JavaScript
medium
188 accepted
80. Proxy I
JavaScript
easy
178 accepted
82. Proxy II
JavaScript
easy
173 accepted
121. Generator return()
JavaScript
medium
165 accepted
130. async
JavaScript
easy
157 accepted
119. return in Generator
JavaScript
medium
135 accepted
78. RegExp
JavaScript
RegExp
medium
128 accepted
125. try...catch...finally 2
JavaScript
medium
113 accepted
128. setTimeout IV
JavaScript
medium
68 accepted
127. JSON.stringify() II
JavaScript
medium
38 accepted
129. Function II
JavaScript
few challengers
16 accepted