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