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JavaScript Quizzes
Test your knowledge of JavaScript the language itself.
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Difficulty
Solved status
1. Promise order
JavaScript
Promise
easy
2. Promise executor
JavaScript
Promise
easy
3. Promise then callbacks
JavaScript
Promise
easy
4. Promise then callbacks II
JavaScript
Promise
easy
5. scope
JavaScript
easy
6. Arrow Function
JavaScript
medium
7. Increment Operator
JavaScript
easy
8. Implicit Coercion I
JavaScript
easy
9. null and undefined
JavaScript
medium
10. Equal
JavaScript
easy
11. Implicit Coercion II
JavaScript
medium
12. arguments
JavaScript
medium
13. Operator precedence
JavaScript
easy
14. Addition vs Unary Plus
JavaScript
easy
15. instanceOf
JavaScript
easy
16. parseInt
JavaScript
easy
17. reduce
JavaScript
medium
18. Promise executor II
JavaScript
easy
19. `this`
JavaScript
easy
20. name for Function expression
JavaScript
medium
21. Array I
JavaScript
medium
22. min max
JavaScript
easy
23. Promise.all()
JavaScript
easy
24. Equality & Sameness
JavaScript
easy
25. zero
JavaScript
easy
26. true or false
JavaScript
easy
27. Hoisting I
JavaScript
easy
28. Hoisting II
JavaScript
easy
29. Hoisting III
JavaScript
easy
30. Equal II
JavaScript
easy
31. Math
JavaScript
easy
32. Hoisting IIII
JavaScript
easy
33. `this` II
JavaScript
easy
34. precedence
JavaScript
easy
35. Implicit Coercion III
JavaScript
easy
36. Promise.prototype.finally()
JavaScript
easy
37. push unshift
JavaScript
easy
38. Hoisting IV
JavaScript
easy
39. var
JavaScript
easy
40. RegExp.prototype.test
JavaScript
easy
41. `this` III
JavaScript
easy
42. Hoisting V
JavaScript
medium
43. JSON.stringify()
JavaScript
medium
44. Function call
JavaScript
easy
45. Hoisting VI
JavaScript
easy
46. Implicit Coercion IV
JavaScript
easy
47. Promise Order II
JavaScript
easy
48. Prototype
JavaScript
easy
49. `this` IV
JavaScript
easy
50. async await
JavaScript
easy
51. method
JavaScript
medium
52. requestAnimationFrame
JavaScript
medium
53. Prototype 2
JavaScript
easy
54. setTimeout(0ms)
JavaScript
easy
55. sparse array
JavaScript
medium
56. to primitive
JavaScript
easy
57. non-writable
JavaScript
easy
58. inherit getter setter
JavaScript
easy
59. override setter
JavaScript
easy
60. postMessage
JavaScript
easy
61. onClick
JavaScript
easy
62. MessageChannel
JavaScript
easy
63. in
JavaScript
easy
64. reference type
JavaScript
easy
65. Function name
JavaScript
easy
66. comma
JavaScript
easy
67. if
JavaScript
easy
68. if II
JavaScript
medium
69. undefined
JavaScript
easy
70. function
JavaScript
easy
71. two-way generator
JavaScript
easy
72. Array length
JavaScript
easy
73. window name
JavaScript
medium
74. Typed Array length
JavaScript
easy
75. meaningless calculation
JavaScript
easy
76. const
JavaScript
medium
77. parseInt 2
JavaScript
easy
78. RegExp
JavaScript
RegExp
medium
79. Equal III
JavaScript
easy
80. Proxy I
JavaScript
easy
81. setTimeout II
JavaScript
easy
82. Proxy II
JavaScript
easy
83. Plus Plus
JavaScript
easy
84. Array.prototype.sort()
JavaScript
medium
85. String.raw()
JavaScript
easy
86. setTimeout III
JavaScript
easy
87. instanceOf 2
JavaScript
easy
88. try...catch
JavaScript
easy
89. let
JavaScript
easy
90. array keys
JavaScript
medium
91. largest Array index
JavaScript
easy
92. NaN
JavaScript
easy
93. string
JavaScript
easy
94. emoji
JavaScript
easy
95. number format
JavaScript
easy
96. comparison
JavaScript
easy
97. `this` V
JavaScript
easy
98. Promise executor IV
Promise
easy
99. closure
JavaScript
easy
100. `var` vs `let`
JavaScript
easy
101. Equal IV
JavaScript
easy
102. Arrow Function II
JavaScript
easy
103. Promise Order III
JavaScript
easy
104. Inheritance
JavaScript
easy
105. typeof
JavaScript
easy
106. Promise.all() II
JavaScript
easy
107. `this` VI
JavaScript
easy
108. property key
JavaScript
easy
109. isNaN()
JavaScript
easy
110. yield
JavaScript
easy
111. falsy
JavaScript
easy
112. Symbol
JavaScript
easy
113. push
JavaScript
easy
114. constructor
JavaScript
easy
115. parseInt II
JavaScript
easy
116. strict
JavaScript
easy
117. `this` VII
JavaScript
easy
118. structuredClone()
JavaScript
easy
119. return in Generator
JavaScript
easy
120. try..catch..finally
JavaScript
easy
121. Generator return()
JavaScript
medium
122. Iterable
JavaScript
easy
123. return in Generator 2
JavaScript
easy
124. comma 2
JavaScript
easy
125. try...catch...finally 2
JavaScript
easy
126. Object.keys()
JavaScript
medium
127. JSON.stringify() II
JavaScript
medium
128. setTimeout IV
JavaScript
medium
129. Function II
JavaScript
easy
130. async
JavaScript
easy
131. return await
JavaScript
easy
132. banana
JavaScript
easy
133. toString
JavaScript
easy
134. Object.groupBy
JavaScript
medium