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JavaScript Quizzes
Test your knowledge of JavaScript the language itself.
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tag: Promise
tag: JavaScript
1. Promise order
JavaScript
Promise
easy
15667 tried
3. Promise then callbacks
JavaScript
Promise
easy
8178 tried
4. Promise then callbacks II
JavaScript
Promise
easy
7501 tried
2. Promise executor
JavaScript
Promise
easy
7317 tried
5. scope
JavaScript
easy
6889 tried
6. Arrow Function
JavaScript
medium
5979 tried
12. arguments
JavaScript
medium
5778 tried
76. const
JavaScript
hard?
5766 tried
8. Implicit Coercion I
JavaScript
easy
5750 tried
7. Increment Operator
JavaScript
easy
5482 tried
9. null and undefined
JavaScript
medium
3905 tried
10. Equal
JavaScript
easy
3867 tried
97. `this` V
JavaScript
easy
3096 tried
93. string
JavaScript
easy
3064 tried
27. Hoisting I
JavaScript
easy
2701 tried
11. Implicit Coercion II
JavaScript
easy
2697 tried
70. function
JavaScript
easy
2669 tried
17. reduce
JavaScript
medium
2610 tried
19. `this`
JavaScript
easy
2366 tried
29. Hoisting III
JavaScript
easy
2237 tried
68. if II
JavaScript
medium
2104 tried
21. Array I
JavaScript
medium
2088 tried
67. if
JavaScript
easy
2078 tried
20. name for Function expression
JavaScript
medium
1939 tried
14. Addition vs Unary Plus
JavaScript
easy
1925 tried
13. Operator precedence
JavaScript
easy
1876 tried
113. push
JavaScript
medium
1867 tried
120. try..catch..finally
JavaScript
easy
1854 tried
28. Hoisting II
JavaScript
easy
1830 tried
117. `this` VII
JavaScript
easy
1801 tried
86. setTimeout III
JavaScript
easy
1801 tried
89. let
JavaScript
easy
1740 tried
69. undefined
JavaScript
easy
1732 tried
41. `this` III
JavaScript
easy
1718 tried
23. Promise.all()
JavaScript
easy
1701 tried
15. instanceOf
JavaScript
easy
1697 tried
84. Array.prototype.sort()
JavaScript
medium
1691 tried
16. parseInt
JavaScript
easy
1656 tried
38. Hoisting IV
JavaScript
easy
1649 tried
61. onClick
JavaScript
easy
1628 tried
88. try...catch
JavaScript
easy
1553 tried
96. comparison
JavaScript
easy
1522 tried
42. Hoisting V
JavaScript
medium
1522 tried
32. Hoisting IIII
JavaScript
easy
1520 tried
81. setTimeout II
JavaScript
easy
1510 tried
47. Promise Order II
JavaScript
easy
1498 tried
50. async await
JavaScript
easy
1459 tried
36. Promise.prototype.finally()
JavaScript
easy
1430 tried
18. Promise executor II
JavaScript
easy
1410 tried
54. setTimeout(0ms)
JavaScript
easy
1409 tried
72. Array length
JavaScript
easy
1401 tried
39. var
JavaScript
easy
1400 tried
114. constructor
JavaScript
easy
1399 tried
94. emoji
JavaScript
easy
1376 tried
100. `var` vs `let`
JavaScript
easy
1353 tried
92. NaN
JavaScript
easy
1348 tried
95. number format
JavaScript
easy
1304 tried
116. strict
JavaScript
easy
1303 tried
33. `this` II
JavaScript
easy
1251 tried
73. window name
JavaScript
medium
1242 tried
22. min max
JavaScript
easy
1240 tried
43. JSON.stringify()
JavaScript
medium
1237 tried
65. Function name
JavaScript
easy
1223 tried
49. `this` IV
JavaScript
easy
1170 tried
55. sparse array
JavaScript
medium
1168 tried
45. Hoisting VI
JavaScript
easy
1159 tried
25. zero
JavaScript
easy
1115 tried
124. comma 2
JavaScript
easy
1088 tried
123. return in Generator 2
JavaScript
easy
1079 tried
99. closure
JavaScript
easy
1067 tried
37. push unshift
JavaScript
easy
1042 tried
91. largest Array index
JavaScript
easy
1040 tried
63. in
JavaScript
easy
1025 tried
26. true or false
JavaScript
easy
1021 tried
111. falsy
JavaScript
easy
1007 tried
90. array keys
JavaScript
medium
997 tried
51. method
JavaScript
medium
997 tried
87. instanceOf 2
JavaScript
easy
995 tried
79. Equal III
JavaScript
easy
983 tried
44. Function call
JavaScript
easy
982 tried
24. Equality & Sameness
JavaScript
easy
978 tried
103. Promise Order III
JavaScript
easy
969 tried
109. isNaN()
JavaScript
easy
967 tried
98. Promise executor IV
Promise
easy
964 tried
64. reference type
JavaScript
easy
956 tried
107. `this` VI
JavaScript
easy
932 tried
105. typeof
JavaScript
easy
929 tried
46. Implicit Coercion IV
JavaScript
easy
926 tried
48. Prototype
JavaScript
easy
924 tried
122. Iterable
JavaScript
easy
914 tried
115. parseInt II
JavaScript
easy
907 tried
60. postMessage
JavaScript
easy
886 tried
30. Equal II
JavaScript
easy
862 tried
106. Promise.all() II
JavaScript
easy
848 tried
126. Object.keys()
JavaScript
medium
847 tried
108. property key
JavaScript
easy
842 tried
102. Arrow Function II
JavaScript
easy
832 tried
83. Plus Plus
JavaScript
easy
825 tried
53. Prototype 2
JavaScript
easy
798 tried
74. Typed Array length
JavaScript
easy
781 tried
118. structuredClone()
JavaScript
easy
769 tried
77. parseInt 2
JavaScript
easy
764 tried
62. MessageChannel
JavaScript
easy
748 tried
130. async
JavaScript
easy
711 tried
85. String.raw()
JavaScript
medium
689 tried
52. requestAnimationFrame
JavaScript
easy
688 tried
34. precedence
JavaScript
easy
684 tried
121. Generator return()
JavaScript
medium
661 tried
112. Symbol
JavaScript
easy
656 tried
78. RegExp
JavaScript
RegExp
medium
649 tried
31. Math
JavaScript
easy
641 tried
56. to primitive
JavaScript
easy
640 tried
35. Implicit Coercion III
JavaScript
easy
602 tried
101. Equal IV
JavaScript
easy
594 tried
66. comma
JavaScript
easy
582 tried
110. yield
JavaScript
easy
577 tried
59. override setter
JavaScript
easy
559 tried
57. non-writable
JavaScript
easy
556 tried
104. Inheritance
JavaScript
easy
555 tried
119. return in Generator
JavaScript
medium
525 tried
82. Proxy II
JavaScript
easy
518 tried
80. Proxy I
JavaScript
easy
504 tried
40. RegExp.prototype.test
JavaScript
easy
503 tried
58. inherit getter setter
JavaScript
easy
471 tried
125. try...catch...finally 2
JavaScript
medium
466 tried
71. two-way generator
JavaScript
easy
420 tried
75. meaningless calculation
JavaScript
easy
408 tried
131. return await
JavaScript
medium
349 tried
128. setTimeout IV
JavaScript
medium
349 tried
127. JSON.stringify() II
JavaScript
medium
277 tried
129. Function II
JavaScript
few challengers
74 tried