What If? chapters

For other instances of this title, see What If (disambiguation).

This explanation may be incomplete or incorrect: Some articles are missing. Remove this notice after making sure all articles are in the table. If you can address this issue, please edit the page! Thanks.

This is a list of all articles featured in Randall Munroe's what if? blog and book series. If the title of a blog article differs from the title in the book, the book's title will be listed next to the original. A similar list can also be found in the archive section of the blog.

Article title	Title in the book	Blog number	What If? chapter	What If? 2 chapter
Relativistic Baseball		1	2
SAT Guessing		2	66
Yoda		3	32
Mole of Moles		4	10
Robot Apocalypse		5
Glass Half Empty		6	26
Everybody Out		7	35
Everybody Jump		8	9
Soul Mates		9	6
Cassini		10
Droppings		11
Raindrop		12	65
Laser Pointer		13	7
Short Answer Section		14
Mariana Trench Explosion		15
Today’s topic: Lightning	Lightning	16	19
Green Cows		17
BB Gun		18
Tie Vote		19
Diamond		20
Machine-Gun Jetpack		21	14
Cost of Pennies		22
Short Answer Section II	Short-Answer Section	23	18
Model Rockets		24
Three Wise Men		25
Leap Seconds		26
Death Rates		27
Steak Drop		28	23
Spent Fuel Pool		29	3
Interplanetary Cessna		30	30
FedEx Bandwidth		31	44
Hubble		32
Ships		33
Twitter		34	50
Hair Dryer		35	11
Cornstarch		36
Supersonic Stereo		37
Voyager		38
Hockey Puck		39	24
Pressure Cooker		40
Go West		41
Longest Sunset		42	52
Train Loop		43
High Throw		44	38
ISS Music Video		45
Bowling Ball		46
Alien Astronomers		47	28
Sunset on the British Empire		48	60
Sunless Earth		49	57
Extreme Boating		50
Free Fall		51	45
Bouncy Balls		52
Drain the Oceans		53	48
Drain the Oceans: Part II		54	49
Random Sneeze Call		55	53
Restraining an Airplane		56
Dropping a Mountain		57
Orbital Speed		58	43
Updating a Printed Wikipedia		59	58
Signs of Life		60
Speed Bump		61	41
Falling with Helium		62	34
Google’s Datacenters on Punch Cards		63
Rising Steadily		64	15
Twitter Timeline Height		65
500 MPH		66
Expanding Earth		67	55
Human Computer		68	21
Facebook of the Dead		69	59
The Constant Groundskeeper		70
Stirring Tea		71	61
Loneliest Human		72	63
Lethal Neutrinos		73	39
Soda Planet		74
Phone Keypad		75
Reading Every Book		76		10
Growth Rate		77
T-rex Calories		78		7
Lake Tea		79
Pile of Viruses		80
Catch!		81		12
Hitting a comet		82
Star Sand		83		16
Paint the Earth		84		14
Rocket Golf		85
Far-Traveling Objects		86
Enforced by Radar		87
Soda Sequestration		88
Tungsten Countertop		89
Great Tree, Great Axe		90
Faucet Power		91
One-Second Day		92		21
Windshield Raindrops		93
Billion-Story Building		94		22
Pyramid Energy		95
$2 Undecillion Lawsuit		96		23
Burning Pollen		97
Blood Alcohol		98		42
Starlings		99
WWII Films		100
Plastic Dinosaurs		101		26
Keyboard Power		102
Vanishing Water		103
Global Snow		104		59
Cannibalism		105
Ink Molecules		106
Letter to Mom		107
Expensive Shoebox		108
Into the Blue		109
Walking New York		110
All the Money		111
Balloon Car		112
Visit Every State		113
Antimatter		114
Into the Sun		115		61
No-Rules NASCAR		116		35
Distant Death		117
Physical Salary		118
Laser Umbrella		119
Alternate Universe What Ifs		120
Frozen Rivers		121
Lava Lamp		122		40
Fairy Demographics		123
Lunar Swimming		124
Bowling Ball		125
Stairs		126
Tug of War		127
Zippo Phone		128
Black Hole Moon		129
Snow Removal		130
Microwaves		131
Hotter than Average		132
Flagpole		133
Space Burial		134
Digging Downward		135
Spiders vs. the Sun		136		44
New Horizons		137
Jupiter Submarine		138
Jupiter Descending		139
Proton Earth, Electron Moon		140		48
Sunbeam		141
Space Jetta		142
Europa Water Siphon		143
Saliva Pool		144		53
Fire from Moonlight		145		51
Stop Jupiter		146
Niagara Straw		147		55
Eat the Sun		148
Pizza Bird		149
Tattooine Rainbow		150
Sun Bug		151
Flood Death Valley		152
Hide the Atmosphere		153
Coast-to-Coast Coasting		154
Toaster vs. Freezer		155
Electrofishing for Whales		156
Earth-Moon Fire Pole		157		58
Global Windstorm			1
Weird (and Worrying) Questions from the What If? Inbox, #1			4
New York–Style Time Machine			5
Periodic Wall of the Elements			8
Weird (and Worrying) Questions from the What If? Inbox, #2			12
The Last Human Light			13
Weird (and Worrying) Questions from the What If? Inbox, #3			16
Orbital Submarine			17
Weird (and Worrying) Questions from the What If? Inbox, #4			20
Little Planet			22
Common Cold			25
Weird (and Worrying) Questions from the What If? Inbox, #5			27
No More DNA			29
Weird (and Worrying) Questions from the What If? Inbox, #6			31
Flyover States			33
Weird (and Worrying) Questions from the What If? Inbox, #7			36
Self-Fertilization			37
Weird (and Worrying) Questions from the What If? Inbox, #8			40
Lost Immortals			42
Weird (and Worrying) Questions from the What If? Inbox, #9			46
Sparta			47
Lego Bridge			51
Weird (and Worrying) Questions from the What If? Inbox, #10			54
Weightless Arrow			56
Stirring Tea			62
Weird (and Worrying) Questions from the What If? Inbox, #11			64
Neutron Bullet			67
Weird (and Worrying) Questions from the What If? Inbox, #12			68
Richter 15			69
Soupiter				1
Helicopter Ride				2
Dangerously Cold				3
Ironic Vaporization				4
Cosmic Road Trip				5
Pigeon Chair				6
Short Answers #1				Unnumbered (between 6 and 7)
Geyser				8
Pew, Pew, Pew				9
Weird & Worrying #1				Unnumbered (between 10 and 11)
Banana Church				11
Lose Weight the Slow and Incredibly Difficult Way				13
Jupiter Comes to Town				15
Swing Set				17
Airliner Catapult				18
Short Answers #2				Unnumbered (between 18 and 19)
Slow Dinosaur Apocalypse				19
Elemental Worlds				20
Star Ownership				24
Tire Rubber				25
Short Answers #3				Unnumbered (between 26 and 27)
Suction Aquarium				27
Earth Eye				28
Build Rome in a Day				29
Mariana Trench Tube				30
Expensive Shoebox				31
MRI Compass				32
Ancestor Fraction				33
Bird Car				34
Weird & Worrying #2				Unnumbered (between 35 and 36)
Vacuum Tube Smartphone				36
Laser Umbrella				37
Eat a Cloud				38
Tall Sunsets				39
Sisyphean Refrigerators				41
Basketball Earth				43
Inhale a Person				45
Candy Crush Lightning				46
Short Answers #4				Unnumbered (between 46 and 47)
Toasty Warm				47
Eyeball				49
Japan Runs an Errand				50
Read All the Laws				52
Weird & Worrying #3				Unnumbered (between 52 and 53)
Snowball				54
Walking Backward in Time				56
Ammonia Tube				57
Short Answers #5				Unnumbered (between 58 and 59)
Dog Overload				60
Sunscreen				62
Walking on the Sun				63
Lemon Drops and Gumdrops				64