BFE
.dev
buy us
a coffee
EN
Practice
Explore
EN
JavaScript Quizzes
Test your knowledge of JavaScript the language itself.
Sort
Difficulty
Solved status
Sort: most accepted
tag: JavaScript
1. Promise order
JavaScript
Promise
easy
4993 accepted
2. Promise executor
JavaScript
Promise
easy
4493 accepted
3. Promise then callbacks
JavaScript
Promise
easy
3239 accepted
5. scope
JavaScript
easy
2850 accepted
4. Promise then callbacks II
JavaScript
Promise
easy
2320 accepted
7. Increment Operator
JavaScript
easy
2315 accepted
8. Implicit Coercion I
JavaScript
easy
1772 accepted
6. Arrow Function
JavaScript
medium
1543 accepted
10. Equal
JavaScript
easy
1409 accepted
93. string
JavaScript
easy
1138 accepted
9. null and undefined
JavaScript
medium
1134 accepted
69. undefined
JavaScript
easy
1050 accepted
97. `this` V
JavaScript
easy
1025 accepted
12. arguments
JavaScript
medium
1016 accepted
13. Operator precedence
JavaScript
easy
1006 accepted
89. let
JavaScript
easy
991 accepted
27. Hoisting I
JavaScript
easy
985 accepted
28. Hoisting II
JavaScript
easy
869 accepted
70. function
JavaScript
easy
856 accepted
86. setTimeout III
JavaScript
easy
851 accepted
11. Implicit Coercion II
JavaScript
easy
799 accepted
29. Hoisting III
JavaScript
easy
795 accepted
39. var
JavaScript
easy
758 accepted
17. reduce
JavaScript
medium
754 accepted
19. `this`
JavaScript
easy
745 accepted
23. Promise.all()
JavaScript
easy
687 accepted
18. Promise executor II
JavaScript
easy
685 accepted
96. comparison
JavaScript
easy
674 accepted
41. `this` III
JavaScript
easy
671 accepted
99. closure
JavaScript
easy
653 accepted
79. Equal III
JavaScript
easy
653 accepted
61. onClick
JavaScript
easy
641 accepted
45. Hoisting VI
JavaScript
easy
622 accepted
67. if
JavaScript
easy
614 accepted
100. `var` vs `let`
JavaScript
easy
607 accepted
94. emoji
JavaScript
easy
606 accepted
15. instanceOf
JavaScript
easy
606 accepted
54. setTimeout(0ms)
JavaScript
easy
604 accepted
14. Addition vs Unary Plus
JavaScript
easy
593 accepted
38. Hoisting IV
JavaScript
easy
588 accepted
120. try..catch..finally
JavaScript
easy
583 accepted
37. push unshift
JavaScript
easy
578 accepted
63. in
JavaScript
easy
574 accepted
33. `this` II
JavaScript
easy
572 accepted
105. typeof
JavaScript
easy
571 accepted
117. `this` VII
JavaScript
easy
567 accepted
111. falsy
JavaScript
easy
562 accepted
47. Promise Order II
JavaScript
easy
560 accepted
76. const
JavaScript
hard?
550 accepted
44. Function call
JavaScript
easy
544 accepted
81. setTimeout II
JavaScript
easy
543 accepted
113. push
JavaScript
medium
533 accepted
16. parseInt
JavaScript
easy
533 accepted
46. Implicit Coercion IV
JavaScript
easy
531 accepted
22. min max
JavaScript
easy
531 accepted
124. comma 2
JavaScript
easy
529 accepted
65. Function name
JavaScript
easy
525 accepted
91. largest Array index
JavaScript
easy
513 accepted
107. `this` VI
JavaScript
easy
508 accepted
72. Array length
JavaScript
easy
504 accepted
49. `this` IV
JavaScript
easy
495 accepted
68. if II
JavaScript
medium
492 accepted
92. NaN
JavaScript
easy
489 accepted
95. number format
JavaScript
easy
470 accepted
88. try...catch
JavaScript
easy
470 accepted
32. Hoisting IIII
JavaScript
easy
465 accepted
50. async await
JavaScript
easy
462 accepted
21. Array I
JavaScript
medium
462 accepted
36. Promise.prototype.finally()
JavaScript
easy
452 accepted
24. Equality & Sameness
JavaScript
easy
445 accepted
20. name for Function expression
JavaScript
medium
440 accepted
114. constructor
JavaScript
easy
438 accepted
115. parseInt II
JavaScript
easy
433 accepted
48. Prototype
JavaScript
easy
432 accepted
53. Prototype 2
JavaScript
easy
430 accepted
84. Array.prototype.sort()
JavaScript
medium
429 accepted
74. Typed Array length
JavaScript
easy
423 accepted
26. true or false
JavaScript
easy
422 accepted
116. strict
JavaScript
easy
419 accepted
103. Promise Order III
JavaScript
easy
418 accepted
106. Promise.all() II
JavaScript
easy
406 accepted
109. isNaN()
JavaScript
easy
401 accepted
123. return in Generator 2
JavaScript
easy
389 accepted
34. precedence
JavaScript
easy
382 accepted
87. instanceOf 2
JavaScript
easy
371 accepted
122. Iterable
JavaScript
easy
368 accepted
42. Hoisting V
JavaScript
medium
367 accepted
102. Arrow Function II
JavaScript
easy
359 accepted
108. property key
JavaScript
easy
341 accepted
64. reference type
JavaScript
easy
339 accepted
60. postMessage
JavaScript
easy
338 accepted
25. zero
JavaScript
easy
337 accepted
30. Equal II
JavaScript
easy
335 accepted
101. Equal IV
JavaScript
easy
322 accepted
66. comma
JavaScript
easy
320 accepted
104. Inheritance
JavaScript
easy
319 accepted
59. override setter
JavaScript
easy
311 accepted
112. Symbol
JavaScript
easy
305 accepted
31. Math
JavaScript
easy
295 accepted
43. JSON.stringify()
JavaScript
medium
293 accepted
40. RegExp.prototype.test
JavaScript
easy
287 accepted
62. MessageChannel
JavaScript
easy
282 accepted
83. Plus Plus
JavaScript
easy
279 accepted
57. non-writable
JavaScript
easy
278 accepted
77. parseInt 2
JavaScript
easy
260 accepted
52. requestAnimationFrame
JavaScript
easy
259 accepted
118. structuredClone()
JavaScript
easy
251 accepted
73. window name
JavaScript
medium
244 accepted
90. array keys
JavaScript
medium
239 accepted
55. sparse array
JavaScript
medium
236 accepted
71. two-way generator
JavaScript
easy
231 accepted
35. Implicit Coercion III
JavaScript
easy
226 accepted
110. yield
JavaScript
easy
223 accepted
58. inherit getter setter
JavaScript
easy
218 accepted
56. to primitive
JavaScript
easy
211 accepted
75. meaningless calculation
JavaScript
easy
208 accepted
85. String.raw()
JavaScript
medium
199 accepted
51. method
JavaScript
medium
198 accepted
126. Object.keys()
JavaScript
medium
196 accepted
130. async
JavaScript
easy
188 accepted
80. Proxy I
JavaScript
easy
179 accepted
82. Proxy II
JavaScript
easy
174 accepted
121. Generator return()
JavaScript
medium
168 accepted
119. return in Generator
JavaScript
medium
138 accepted
78. RegExp
JavaScript
RegExp
medium
129 accepted
125. try...catch...finally 2
JavaScript
medium
116 accepted
128. setTimeout IV
JavaScript
medium
74 accepted
127. JSON.stringify() II
JavaScript
medium
43 accepted
129. Function II
JavaScript
few challengers
20 accepted
131. return await
JavaScript
11 accepted