The True Size Of
53 comments
·April 26, 2025ivanjermakov
Related: amazing video about map projections: https://youtu.be/bpp0xCknQAQ?si=AL-Qt36AeUH_oSeI
fhennig
I really enjoy this! I wish it would also support cities, it would help me get a better sense of the size of a city to compare it to one I'm familiar with already. But I guess city limits are less well defined that country limits. Anyway, great project!
lpribis
Use this site for that https://acme.com/same_scale/. It lets you compare any two map views at the same scale.
zamadatix
That site only seems lock the zoom value of the two maps together, not correct for distortions. E.g. zoom in on Svalbard on one side and the Democratic Republic of the Congo on the other. Svalbard appears larger despite being many times smaller. This means if you zoom into Longyearbyen it will appear several times larger than it should compared to say Kinshasa.
Longyearbyen is a pathological example but it's quite easy to end up thinking a city in the UK is ~1.75 linearly and ~3x by area compared to one on the equator using this site.
xiconfjs
+1 for cities
andrewl
I've been using, and sharing, this site for several years. I think it's excellent. The two things I'd like to see are the provinces, at least in larger countries, and large bodies of water. I'd like to be able to drag Ontario, Lake Superior, the Caspian Sea, New South Wales, and so on, around the way you can with countries and US states.
diggernet
Pretty neat. One tip it took me a while to realize is that after you tap on a country, the compass rose (now the same color as the country) can be used to rotate it.
But why do countries rotate to the left as you drag them north and rotate to the right as you drag them south?
bregma
It's a widely observed phenomenon that as a country start to go south it moves to the right.
This explains much of the current global political situation.
geor9e
I think part of that is an illusion, since for something bowing upwards, the usualy anchor point of top left seems rotated clockwise.
But there is still a real rotation - look at wyoming or colorado for a perfect rectangle. My guess is the div element isn't quite centered - perhaps too much padding on the right edge, causing the center point to be off to the right. So when it bows you get the rotation bias
hereaiham
What a nice well made tool. I was shocked how massive Algeria is! Maybe larger than half of Europe. And Tunisia which is a tiny country in my head, seems to be not tiny at all.
EA
Algeria is about 23.4% the size of Europe.
flerchin
It's interesting to me how the large countries are roughly similarly sized. Canada, Australia, US, Brazil, China, Russia, India are all within a factor of 2, and it shows when you drag it across eachother. India and Russia as outliers slightly.
lucianbr
This is a tautology. You defined the category "large countries" such that they are as you say, close in size to each other.
Miraltar
Russia is literally 5 times bigger than India
xg15
Mercator projection striking again.
The largest surprise for me (besides the massive size of Africa and South America of course) was that Australia has roughly the same area as the entire US. Somehow I had always imagined it smaller.
HdS84
I wish schools would stop using it so much. Mercator is useful, yes. But having good size comparisons is much more important for most everyday tasks.
Sharlin
It's useful for navigation in the open ocean without satnav or even a chronometer, which is what it was designed for in the 1500s. Not for much else.
Is the use of Mercator in schools common, globally? Based on what I've read on the internet it's common in the US, but I have no idea about other countries. In Finland I think I only ever saw Robinson or Winkel-tripel type compromise projections. Mercator was maybe used as an example of how projections distort things.
HdS84
German is Mercator only. Learned about different projection on the internet years after school
scbrg
Huh. Swede here. Went to school in the 80:ies and 90:ies. Only ever saw Mercator. Perhaps things have changed since.
QuesnayJr
It preserves angles, which is what makes it useful in navigation. Mercator is bad at relative sizes for places far apart, but when you look at a small patch shapes are less distorted. For that reason, online maps use a version of Mercator.
xg15
I wonder if Mercator maps that aren't aligned with the equator would already do the trick. (pinging Randall Munroe)
pif
A flat map on a wall does not take any three-dimensional space. You can't say the same for a globe, though!
alluro2
Wow - in my head, Australia was somehow ~20-25% the size of US (I'm from Europe) - really surprising, and shows how misleading the projection can be in this regard.
boxed
So much tech that can be accomplished by just using Waterman butterfly, Peters, Dymaxion or any of a host of other projections.
izzydata
It's interesting how Russia appears to only be about twice as large as the United States or China, but on a typical map it looks at least 3-4 times larger.
mijoharas
If you drag something large over so it covers the south pole the shading can invert so that only the region covering the south pole is unshaded.
That's how I proved that the actual size of Australia is approximately 90% of the area of the globe. Who knew the mercator projection could be so confusing! :)
Vagantem
Gall Peters Projection scene (From "The West Wing" S2E16) https://www.youtube.com/watch?v=vVX-PrBRtTY
I feel very lucky to have grown up with a huge (~ 75 cm diameter) globe as a centerpiece in the living room; I never ended up with Mercator-derived misconceptions in the first place.