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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
5067 accepted
2. Promise executor
JavaScript
Promise
easy
4561 accepted
3. Promise then callbacks
JavaScript
Promise
easy
3293 accepted
5. scope
JavaScript
easy
2893 accepted
4. Promise then callbacks II
JavaScript
Promise
easy
2359 accepted
7. Increment Operator
JavaScript
easy
2349 accepted
8. Implicit Coercion I
JavaScript
easy
1800 accepted
6. Arrow Function
JavaScript
medium
1570 accepted
10. Equal
JavaScript
easy
1432 accepted
9. null and undefined
JavaScript
medium
1150 accepted
93. string
JavaScript
easy
1144 accepted
69. undefined
JavaScript
easy
1065 accepted
12. arguments
JavaScript
medium
1038 accepted
97. `this` V
JavaScript
easy
1029 accepted
13. Operator precedence
JavaScript
easy
1026 accepted
89. let
JavaScript
easy
1000 accepted
27. Hoisting I
JavaScript
easy
998 accepted
28. Hoisting II
JavaScript
easy
883 accepted
70. function
JavaScript
easy
860 accepted
86. setTimeout III
JavaScript
easy
854 accepted
11. Implicit Coercion II
JavaScript
easy
811 accepted
29. Hoisting III
JavaScript
easy
810 accepted
39. var
JavaScript
easy
770 accepted
17. reduce
JavaScript
medium
764 accepted
19. `this`
JavaScript
easy
756 accepted
23. Promise.all()
JavaScript
easy
703 accepted
18. Promise executor II
JavaScript
easy
694 accepted
41. `this` III
JavaScript
easy
682 accepted
96. comparison
JavaScript
easy
677 accepted
99. closure
JavaScript
easy
668 accepted
79. Equal III
JavaScript
easy
666 accepted
61. onClick
JavaScript
easy
645 accepted
45. Hoisting VI
JavaScript
easy
633 accepted
67. if
JavaScript
easy
620 accepted
15. instanceOf
JavaScript
easy
618 accepted
100. `var` vs `let`
JavaScript
easy
616 accepted
54. setTimeout(0ms)
JavaScript
easy
613 accepted
94. emoji
JavaScript
easy
610 accepted
14. Addition vs Unary Plus
JavaScript
easy
605 accepted
38. Hoisting IV
JavaScript
easy
599 accepted
120. try..catch..finally
JavaScript
easy
597 accepted
37. push unshift
JavaScript
easy
592 accepted
105. typeof
JavaScript
easy
581 accepted
33. `this` II
JavaScript
easy
581 accepted
63. in
JavaScript
easy
578 accepted
111. falsy
JavaScript
easy
575 accepted
117. `this` VII
JavaScript
easy
574 accepted
47. Promise Order II
JavaScript
easy
569 accepted
124. comma 2
JavaScript
easy
556 accepted
76. const
JavaScript
hard?
556 accepted
44. Function call
JavaScript
easy
555 accepted
16. parseInt
JavaScript
easy
547 accepted
81. setTimeout II
JavaScript
easy
546 accepted
46. Implicit Coercion IV
JavaScript
easy
543 accepted
113. push
JavaScript
medium
541 accepted
22. min max
JavaScript
easy
541 accepted
65. Function name
JavaScript
easy
530 accepted
91. largest Array index
JavaScript
easy
516 accepted
107. `this` VI
JavaScript
easy
514 accepted
72. Array length
JavaScript
easy
506 accepted
49. `this` IV
JavaScript
easy
503 accepted
68. if II
JavaScript
medium
496 accepted
92. NaN
JavaScript
easy
493 accepted
88. try...catch
JavaScript
easy
475 accepted
95. number format
JavaScript
easy
474 accepted
32. Hoisting IIII
JavaScript
easy
470 accepted
50. async await
JavaScript
easy
469 accepted
21. Array I
JavaScript
medium
469 accepted
36. Promise.prototype.finally()
JavaScript
easy
462 accepted
24. Equality & Sameness
JavaScript
easy
454 accepted
20. name for Function expression
JavaScript
medium
449 accepted
114. constructor
JavaScript
easy
442 accepted
115. parseInt II
JavaScript
easy
439 accepted
48. Prototype
JavaScript
easy
438 accepted
53. Prototype 2
JavaScript
easy
433 accepted
84. Array.prototype.sort()
JavaScript
medium
431 accepted
103. Promise Order III
JavaScript
easy
428 accepted
26. true or false
JavaScript
easy
428 accepted
74. Typed Array length
JavaScript
easy
426 accepted
116. strict
JavaScript
easy
425 accepted
106. Promise.all() II
JavaScript
easy
413 accepted
109. isNaN()
JavaScript
easy
409 accepted
34. precedence
JavaScript
easy
392 accepted
123. return in Generator 2
JavaScript
easy
390 accepted
87. instanceOf 2
JavaScript
easy
375 accepted
122. Iterable
JavaScript
easy
374 accepted
42. Hoisting V
JavaScript
medium
373 accepted
98. Promise executor IV
Promise
easy
369 accepted
102. Arrow Function II
JavaScript
easy
366 accepted
108. property key
JavaScript
easy
344 accepted
64. reference type
JavaScript
easy
343 accepted
25. zero
JavaScript
easy
343 accepted
60. postMessage
JavaScript
easy
342 accepted
30. Equal II
JavaScript
easy
339 accepted
104. Inheritance
JavaScript
easy
327 accepted
101. Equal IV
JavaScript
easy
326 accepted
66. comma
JavaScript
easy
326 accepted
59. override setter
JavaScript
easy
318 accepted
112. Symbol
JavaScript
easy
308 accepted
31. Math
JavaScript
easy
301 accepted
43. JSON.stringify()
JavaScript
medium
298 accepted
40. RegExp.prototype.test
JavaScript
easy
294 accepted
62. MessageChannel
JavaScript
easy
285 accepted
57. non-writable
JavaScript
easy
282 accepted
83. Plus Plus
JavaScript
easy
281 accepted
77. parseInt 2
JavaScript
easy
263 accepted
52. requestAnimationFrame
JavaScript
easy
263 accepted
118. structuredClone()
JavaScript
easy
256 accepted
73. window name
JavaScript
medium
249 accepted
55. sparse array
JavaScript
medium
241 accepted
90. array keys
JavaScript
medium
240 accepted
71. two-way generator
JavaScript
easy
236 accepted
35. Implicit Coercion III
JavaScript
easy
231 accepted
110. yield
JavaScript
easy
225 accepted
130. async
JavaScript
easy
222 accepted
58. inherit getter setter
JavaScript
easy
220 accepted
56. to primitive
JavaScript
easy
215 accepted
75. meaningless calculation
JavaScript
easy
209 accepted
126. Object.keys()
JavaScript
medium
207 accepted
51. method
JavaScript
medium
201 accepted
85. String.raw()
JavaScript
medium
200 accepted
80. Proxy I
JavaScript
easy
184 accepted
82. Proxy II
JavaScript
easy
178 accepted
121. Generator return()
JavaScript
medium
169 accepted
119. return in Generator
JavaScript
medium
140 accepted
78. RegExp
JavaScript
RegExp
medium
131 accepted
125. try...catch...finally 2
JavaScript
medium
126 accepted
128. setTimeout IV
JavaScript
medium
78 accepted
131. return await
JavaScript
medium
56 accepted
127. JSON.stringify() II
JavaScript
medium
48 accepted
129. Function II
JavaScript
few challengers
21 accepted