Randall Munroe
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xkcd.com
Randall Munroe
@xkcd.com
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xkcd.com
Earthquake Prediction Flowchart

xkcd.com/3165/
Comic. Someone is claiming to predict the exact date of a future earthquake. Should you listen? [flowchart: start] → NO (There are big earthquakes constantly, so if anyone ever *does* figure this out, it will be immediately obvious that their method works and then the world’s seismologists will not shut up about it. You won’t need this flowchart.)
November 10, 2025 at 8:55 PM
xkcd.com
Metric Tip

xkcd.com/3164/
Comic. PERSON 1 with white hat: How tall are you? PERSON 2: 5ft 24cm [caption] When switching to metric, make the process easier by doing it in steps.
November 6, 2025 at 11:33 PM
xkcd.com
Repair Video

xkcd.com/3163/
Comic. [Person sitting at desk with laptop with machine labeled E-21 making “click click” noises on the floor behind] VOICE FROM LAPTOP: Hey all! Does your E-21 humidifier make an annoying clicking noise? Mine did, but I finally figured out that there’s an easy fix, so I made this video in case anyone else… PERSON AT DESK: Oh my god. Yes. *Yes.* [caption] I know there’s more important work in the world, but I feel like these people deserve, at minimum a statue.
November 5, 2025 at 10:03 PM
xkcd.com
Heart Mountain

xkcd.com/3162/
4-panel comic. (1) PERSON 1: We haven’t checked in on the geology department for a while. I wonder if they’re doing okay. (2) PERSON 2 with ponytail: I’ll go see what they’re up to. (3) [Person 2 opens door to room where a person is gesturing at a projector screen and explaining to two other people] PERSON 3: 49 million years ago, Heart Mountain, Wyoming slid sideways 15 miles like a giant stone hovercraft. (4) PERSON 2 [returning to Person 1]: ...They’re not okay. OFF-PANEL PERSON: Hey, *you* come up with a better explanation!
November 4, 2025 at 8:12 PM
xkcd.com
Airspeed

xkcd.com/3161/
Comic. [Two people in a hot air balloon] PERSON 1: 0 mph... 0 mph... Ooh, 1 mph with that last gust... 0 mph... 1 mph... 1 mph... *2 mph!!!* PERSON 2: *Yessss!* [caption] Breaking the hot air balloon level-flight airspeed record
October 30, 2025 at 10:05 PM
xkcd.com
Document Forgery

xkcd.com/3160/
Comic. [diploma from East State University for Doctor of Philosophy in Document Forgery] [caption] If you put one of these up in your office, and no one notices, you’ve earned it.
October 28, 2025 at 8:00 PM
xkcd.com
Continents

xkcd.com/3159/
Comic. [two connected spacecraft hovering in space above the Earth] Houston, the view is superb. We can see the continents spread out below us, right where they’ve been since the Earth formed. [caption] I still can’t believe we developed spaceflight before we figured out that the continents moved.
October 27, 2025 at 8:05 PM
xkcd.com
Shielding Chart

xkcd.com/3158/
Comic. Confusion matrix showing renditions of different combinations, colored yellow, tan, or gray. [Air: gamma rays Y, neutrons Y, alpha particles G, light Y, sound Y, heat Y, swords Y, toxic dust Y, radio Y, sharks G] [Lead: gamma rays G, neutrons T, alpha particles G, light G, Sound Y, heat Y, swords G, toxic dust T, radio G, sharks G] [Water: gamma rays T, neutrons G, alpha particles G, light T, sound Y, heat Y, swords Y, toxic dust Y, radio G, sharks Y] [Vacuum: gamma rays Y, neutrons Y, alpha particles Y, light Y, sound G, heat T, swords Y, toxic dust Y, radio Y, sharks G] [Oven mitts: gamma rays Y, neutrons Y, alpha particles G, light G, sound T, heat G, swords Y, toxic dust Y, radio Y, sharks Y] [Armor: gamma rays Y, neutrons Y, alpha particles G, light G, sound Y, heat Y, swords G, toxic dust Y, radio G, sharks T] [Biohazard suit: gamma rays Y, neutrons Y, alpha particles G, light G, sound Y, heat Y, swords Y, toxic dust G, radio Y, sharks Y] [Faraday cage: gamma rays Y, neutrons Y, alpha particles Y, light Y, sound Y, heat Y, swords Y, toxic dust Y, radio G, sharks Y] [Shark cage: gamma rays Y, neutrons Y, alpha particles Y, light Y, sound Y, heat Y, swords Y, toxic dust Y, radio Y, sharks G]
October 23, 2025 at 8:10 PM
xkcd.com
Emperor Palpatine

xkcd.com/3157/
Comic. Scatter chart with Emperor Palpatine character age on Y axis and Ian McDiarmid age during filming on X axis. Plot with descending arrow beginning from Return of the Jedi (emperor age 90, McDiarmid age 40) → Revenge of the Sith, Attack of the Clones, and The Phantom Menace (emperor age 50-70, McDiarmid age 50-60) → The Rise of Skywalker (cloned body, undefined age) with a gradient vertical line (McDiarmid age over 70) → Now (emperor age under 10, McDiarmid age over 80). [caption] To continue the trend, they should make a Star Wars movie where 81-year-old Ian McDiarmid plays the emperor as a toddler.
October 22, 2025 at 8:07 PM
xkcd.com
Can you drive west to lengthen the sunset?

What the latest What If? video in collaboration with @minuteearth.bsky.social!

www.youtube.com/watch?v=U8F7...
Can you drive west to lengthen the sunset?
YouTube video by xkcd's What If?
www.youtube.com
October 21, 2025 at 7:19 PM
xkcd.com
Planetary Rings

xkcd.com/3156/
Comic. Two-column table. Column A lists planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Column B has checkmark boxes for whether the planets have rings: the outer planets’ boxes are checked, and Earth has a red check. [Earth with a ring with an array pf points around it. An arrow labeled “Geostationary Satellite Bel”t points to the ring.] [caption] Astronomy fact: A century ago, Earth didn’t have rings, but we have one now! It’s where all the satellite dishes are pointed.
October 20, 2025 at 10:44 PM
xkcd.com
Physics Paths

xkcd.com/3155/
Vertical comic structured like flow chart. (1) Einstein had an insight that overturned physics, thus proving his value. (2) I hope *I* have value. I’ll try to have an insight that overturns physics, to check. (3) [Time Passes] (4) Oh no! My insight didn’t overturn physics! But I don’t think I’m worthless… [arrows to two different options] (5a) Healthy Path: Maybe this was not a well-thought-out test of my value. (5b) Path of Ruin: The establishment must be *suppressing* my insight!
October 16, 2025 at 8:12 PM
xkcd.com
Physics Insight

xkcd.com/3154/
Comic. PERSON: Sure, when *Einstein* suggests using the Lorentz transform to explain the connection between velocity and time, people call him a genius. But when *I* suggest it, it’s “basic physics” and “undergraduate stuff.” PERSON 2 with white hat: Such a double standard!
October 15, 2025 at 8:14 PM
xkcd.com
Hot Water Balloon

xkcd.com/3153/
Comic. [Giant balloon reminiscent of a hot air balloon but wavy and laying on the ground with “bloop” “bloop” sound effects. Two people are in a basket attached to one end of the balloon.] [caption] Hot water balloon rides turn out to be significantly less romantic than the air kind.
October 14, 2025 at 7:53 PM
xkcd.com
Skateboard

xkcd.com/3152/
4-panel comic. (1) [person in the sky unpacks skateboard from parachute bag] I guess this is on me. I should really keep my skateboarding gear and my parachutes in different-looking bags. (2) [person looking down at skateboard as they fall] (3) [person falling wile holding skateboard in one hand and phone making “beep beep” sound in the other] (4) (person still falling with skateboard, now talking on phone] Hello, Pro Skate Parks LLC? I’d like to place an extremely expedited order for a 600-foot halfpipe.
October 9, 2025 at 9:40 PM
xkcd.com
Window Screen

xkcd.com/3151/
4-panel comic. (1) [person in front of window, shaped like a trapezoid with a curved top] This weekend, I had to make an oversized screen for a porch window. (2) [person sitting with hands on head surrounded by images of assorted equations and measurements] It involved countless tiny problems, each somehow way harder than it should be. Oblique angles. Curved edges. Noncoplanarity. (3) [person in front of window with screen on it, with building detritus strewn on the ground] ...I solved them all. I measured precisely. I did trigonometry. I made custom parts. And it fit *perfectly.* No gaps, no ripples. (4) [person typing at computer] I know that your foundation normally limits its purview to physics, medicine, peace, chemistry, and literature. However, if you review the attached photos showing how well the screen fits into the...
October 7, 2025 at 7:43 PM
xkcd.com
Ping

xkcd.com/3150/
4-panel comic. (1) [person finds bottle on shore] (2) [person reads message from inside bottle: ICMP ECHO REQUEST...] (3) [person writes on message ICMP ECHO REPLY...] (4) [person puts bottle back in water and leaves]
October 7, 2025 at 2:24 AM
xkcd.com
Measure Twice, Cut Once

xkcd.com/3149/
Comic. “Measure [Twice], cut [Once]” -Carpenty Proverb. [Scatter plot with number of measurements on y axis and number of cuts on x axis. Points in a descending line on graph: surveyor, surgeon, good carpenter, careless carpenter, really bad carpenter, serial killer]
October 3, 2025 at 5:36 PM
xkcd.com
100% All Achievements

xkcd.com/3148/
Comic. PERSON 1 to person with white hat: I finished all the gen-ed back in 2010, and I’m up to the 400-level courses in most departments. But now one of my advisors is saying I “can’t have more than 20 majors” and “need to graduate next year.” It’s outrageous! [caption] My university is making it really hard to finish a 100% all achievements speedrun.
October 1, 2025 at 8:51 PM
xkcd.com
Could we survive eating only humans?

Watch the latest What If? video collaboration with @minuteearth.bsky.social!

youtu.be/PUtI3xoaHx0
Could we survive eating only humans?
YouTube video by xkcd's What If?
youtu.be
September 30, 2025 at 10:51 PM
xkcd.com
Hiking

xkcd.com/3147/
Comic. [Two people hiking up mountain] PERSON 1: Okay, we’re nearing the next downhill segment I’ll put in the order. ...Confirming start and end points… Submitted! [water slide being dropped from above by drones] PERSON 2 with long hair: Look, here it comes! [Waterslide positioned on downhill slope of mountain with both people riding down] BOTH: Wheeee [Waterslide carried back into the air] [Both people continuing to hike up next slope] [caption] On-demand waterslide delivery has really improved the whole hiking experience.
September 29, 2025 at 7:17 PM
xkcd.com
Fantastic Four

xkcd.com/3146/
Comic. [Person with ponytail talking to a second person.] PERSON 1: In the new *Fantastic Four* movie, their ship doesn’t have enough fuel to get home and Sue Storm goes into labor, so they slingshot around a neutron star and fire their engines at periapsis—as Sue has her baby—to get a boost. PERSON 2: Ah yes, the Obirth effect.
September 25, 2025 at 7:52 PM
xkcd.com
Piercing

xkcd.com/3145/
Comic. [Large panel showing curve of Earth with upward opening curve below the surface labeled “constant curvature borehole.” Two smaller overlaid panels show (1) People next to machine on tracks with a tube pointed to the ground labeled “directional drilling rig” and (2) Earth with a ring embedded in it.] [caption] Good news: Geologists have decided that Earth is finally old enough to get its first lithosphere piercing!
September 23, 2025 at 6:58 PM
xkcd.com
Phase Changes

xkcd.com/3144/
2-panel comic. (1) Phase Changes in Theory. PERSON with short hair: As you can see, when water is cooled to below 0°C, it changes from a liquid to a solid. [bowl of even layer of ice] (2) Phase Changes in Practice. PERSON: When water freezes, it sometimes sends out long weird spikes. Physics tells us the water is “trying to give us a present.” [bowl with weird ice shapes jutting upwards]
September 22, 2025 at 10:53 PM
xkcd.com
Question Mark

xkcd.com/3143/
Comic. PERSON 1: That movie was so good. Maybe even the greatest movie of all time question mark? PERSON 2: Yeah comma, but you said that about italics *Charlie’s Angels Colon: Full Throttle* period. Paragraph break. I question your judgement period. [caption] When people say “question mark” out loud as a rhetorical device, it always makes me want to say my other punctuation and formatting too.
September 18, 2025 at 8:14 PM