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JavaScript Quizzes
Test your knowledge of JavaScript the language itself.
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Difficulty
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Sort: most tried
1. Promise order
JavaScript
Promise
easy
15136 tried
3. Promise then callbacks
JavaScript
Promise
easy
7885 tried
4. Promise then callbacks II
JavaScript
Promise
easy
7213 tried
2. Promise executor
JavaScript
Promise
easy
7040 tried
5. scope
JavaScript
easy
6651 tried
6. Arrow Function
JavaScript
medium
5754 tried
76. const
JavaScript
hard?
5650 tried
12. arguments
JavaScript
medium
5538 tried
8. Implicit Coercion I
JavaScript
easy
5532 tried
7. Increment Operator
JavaScript
easy
5262 tried
9. null and undefined
JavaScript
medium
3779 tried
10. Equal
JavaScript
easy
3717 tried
97. `this` V
JavaScript
easy
3038 tried
93. string
JavaScript
easy
2995 tried
70. function
JavaScript
easy
2611 tried
27. Hoisting I
JavaScript
easy
2602 tried
11. Implicit Coercion II
JavaScript
easy
2537 tried
17. reduce
JavaScript
medium
2509 tried
19. `this`
JavaScript
easy
2273 tried
29. Hoisting III
JavaScript
easy
2117 tried
68. if II
JavaScript
medium
2067 tried
67. if
JavaScript
easy
2024 tried
21. Array I
JavaScript
medium
2002 tried
20. name for Function expression
JavaScript
medium
1862 tried
14. Addition vs Unary Plus
JavaScript
easy
1829 tried
13. Operator precedence
JavaScript
easy
1796 tried
113. push
JavaScript
medium
1793 tried
86. setTimeout III
JavaScript
easy
1763 tried
28. Hoisting II
JavaScript
easy
1751 tried
117. `this` VII
JavaScript
easy
1726 tried
120. try..catch..finally
JavaScript
easy
1706 tried
89. let
JavaScript
easy
1686 tried
69. undefined
JavaScript
easy
1676 tried
84. Array.prototype.sort()
JavaScript
medium
1657 tried
41. `this` III
JavaScript
easy
1655 tried
23. Promise.all()
JavaScript
easy
1629 tried
15. instanceOf
JavaScript
easy
1622 tried
61. onClick
JavaScript
easy
1599 tried
38. Hoisting IV
JavaScript
easy
1590 tried
16. parseInt
JavaScript
easy
1570 tried
88. try...catch
JavaScript
easy
1522 tried
96. comparison
JavaScript
easy
1493 tried
81. setTimeout II
JavaScript
easy
1483 tried
42. Hoisting V
JavaScript
medium
1475 tried
32. Hoisting IIII
JavaScript
easy
1466 tried
47. Promise Order II
JavaScript
easy
1450 tried
50. async await
JavaScript
easy
1395 tried
36. Promise.prototype.finally()
JavaScript
easy
1376 tried
54. setTimeout(0ms)
JavaScript
easy
1373 tried
72. Array length
JavaScript
easy
1361 tried
39. var
JavaScript
easy
1357 tried
94. emoji
JavaScript
easy
1353 tried
18. Promise executor II
JavaScript
easy
1348 tried
114. constructor
JavaScript
easy
1342 tried
92. NaN
JavaScript
easy
1311 tried
95. number format
JavaScript
easy
1289 tried
100. `var` vs `let`
JavaScript
easy
1267 tried
116. strict
JavaScript
easy
1263 tried
73. window name
JavaScript
medium
1213 tried
33. `this` II
JavaScript
easy
1207 tried
22. min max
JavaScript
easy
1192 tried
65. Function name
JavaScript
easy
1189 tried
43. JSON.stringify()
JavaScript
medium
1158 tried
55. sparse array
JavaScript
medium
1128 tried
49. `this` IV
JavaScript
easy
1127 tried
45. Hoisting VI
JavaScript
easy
1123 tried
123. return in Generator 2
JavaScript
easy
1039 tried
25. zero
JavaScript
easy
1033 tried
91. largest Array index
JavaScript
easy
1020 tried
37. push unshift
JavaScript
easy
1009 tried
99. closure
JavaScript
easy
996 tried
63. in
JavaScript
easy
996 tried
124. comma 2
JavaScript
easy
988 tried
90. array keys
JavaScript
medium
979 tried
26. true or false
JavaScript
easy
973 tried
87. instanceOf 2
JavaScript
easy
969 tried
51. method
JavaScript
medium
968 tried
44. Function call
JavaScript
easy
939 tried
79. Equal III
JavaScript
easy
936 tried
111. falsy
JavaScript
easy
934 tried
24. Equality & Sameness
JavaScript
easy
934 tried
64. reference type
JavaScript
easy
933 tried
98. Promise executor IV
Promise
easy
921 tried
109. isNaN()
JavaScript
easy
917 tried
48. Prototype
JavaScript
easy
907 tried
103. Promise Order III
JavaScript
easy
906 tried
46. Implicit Coercion IV
JavaScript
easy
888 tried
115. parseInt II
JavaScript
easy
878 tried
105. typeof
JavaScript
easy
876 tried
107. `this` VI
JavaScript
easy
874 tried
60. postMessage
JavaScript
easy
860 tried
122. Iterable
JavaScript
easy
855 tried
30. Equal II
JavaScript
easy
818 tried
108. property key
JavaScript
easy
813 tried
83. Plus Plus
JavaScript
easy
802 tried
102. Arrow Function II
JavaScript
easy
790 tried
106. Promise.all() II
JavaScript
easy
786 tried
53. Prototype 2
JavaScript
easy
786 tried
74. Typed Array length
JavaScript
easy
767 tried
77. parseInt 2
JavaScript
easy
751 tried
118. structuredClone()
JavaScript
easy
744 tried
126. Object.keys()
JavaScript
medium
736 tried
62. MessageChannel
JavaScript
easy
731 tried
85. String.raw()
JavaScript
medium
681 tried
52. requestAnimationFrame
JavaScript
easy
664 tried
34. precedence
JavaScript
easy
657 tried
121. Generator return()
JavaScript
medium
649 tried
78. RegExp
JavaScript
RegExp
medium
632 tried
112. Symbol
JavaScript
easy
628 tried
56. to primitive
JavaScript
easy
618 tried
31. Math
JavaScript
easy
609 tried
35. Implicit Coercion III
JavaScript
easy
568 tried
101. Equal IV
JavaScript
easy
563 tried
66. comma
JavaScript
easy
560 tried
110. yield
JavaScript
easy
553 tried
59. override setter
JavaScript
easy
541 tried
57. non-writable
JavaScript
easy
538 tried
104. Inheritance
JavaScript
easy
526 tried
82. Proxy II
JavaScript
easy
510 tried
80. Proxy I
JavaScript
easy
490 tried
119. return in Generator
JavaScript
medium
489 tried
40. RegExp.prototype.test
JavaScript
easy
485 tried
58. inherit getter setter
JavaScript
easy
463 tried
130. async
JavaScript
easy
423 tried
71. two-way generator
JavaScript
easy
403 tried
75. meaningless calculation
JavaScript
easy
402 tried
125. try...catch...finally 2
JavaScript
medium
393 tried
128. setTimeout IV
JavaScript
medium
255 tried
127. JSON.stringify() II
JavaScript
medium
186 tried
129. Function II
JavaScript
few challengers
50 tried