I've got an old laptop lying around, but it's HDD has conked.
The laptop has a SDcard reader, so was wondering if I could install Ubuntu on an 8GB SD card I had, and still get things up and running.

Don't plan on using it for much - mostly Python scripting, and browsing the Internet.

Was wondering if 8GB is enough for the install, and if there's anything I need to keep in mind while installing and during use.

Came across this minimal install page. But it seems to be for 18.04 and no longer seems to be supported?
Any idea if there's something like this for 20 or 21?

Also open to other Linux distros, but I'm most comfortable with Ubuntu and would prefer to stick to that.

Was Googling around and came across Porteus - a low footprint Linux. Was wondering if anyone has experience with or similar distros and whether it's recommended I go for it, or stick to Ubuntu?

What is the make and model number of your laptop?

Is it 32 or 64 bit? How much RAM?

Can the laptop boot from the SD card? Is the max SD card size that can be read by the reader 8GB?

It's a HP laptop. This is the model.
8GB RAM, 64-bit.
It can boot from the SD card. Not sure if 8 GB is the max, but I have an 8 GB card lying around, so I wanted to use that.

Some of the smaller distributions use light weight apps and not Gnome which is the default Ubuntu desktop.

Xbuntu uses xfce desktop which requires 7.5 GB hard drive space.

antix would fit on an 8GB card.

If the laptop runs ok otherwise I might consider buying a small 128 GB SSD SATA drive.

Came across Bodhi Linux. Is that something that would work here, or is Antix a better option?
Xubuntu says it needs 8.6 gb, so seems just out of my range.

Bodhi needs a min of 5GB hard drive space.

It will work on your system. The standard install will let you add pick what you want.

I have an HP 650 loaded with antiX at 7GB. You are pushing it with an 8GB card, can be used to check if method works.

Edit: The installation included about 2.5GB of personal files, so the actual install could be as low as 4.5GB. It's enough space to run a system.

OP, I think you received some valid advice on distro choice.
So forgive me for going slightly OT -
why not simply replace the hard drive? I'm sure a significantly larger (than 8GB) hd can be had for next to nothing (if you don't have one lying around). And even the slowest platter should still be faster than an SD card...

Seems like a nice and not too old laptop otherwise, so a little effort / spending a few credits surely is justified?

SD-Card limit may be "SDHC" = 32 GB.
A cheap 120 GB SATA SSD costs about 25 €, is faster than any SDHC card and has enough place for a Linux distro.
I'm using "Patriot Burst 120 GB" SATA SSDs in elder machines with SATA 3.0 GB/s controllers.

Fair point. Just wanted to see if this was a valid option that would put an old SD card to good use. Don't plan on using this laptop for anything heavy duty, so might be a good learning experience.

SD card is Class 10, so 10mbps is the data transfer limit. Wonder if that's going to be a pain though.

No doubt it's a valid question - and you got good answers: choose a distro small enough to fit on 8GB, with room to spare for personal files.
Read or write?
Is it around the same as a good USB3 stick? That should be bearable, at least with a light distro, people say.

The only way I'd use some large distro like that on 8G might be to use a live with persistence. That way you easily get a compressed filesystem. You could do a full install to a compressed filesystem other ways but it isn't overly easy.

I don't know if any of the others run from RAM, but I'd reckon that Porteus might be the go for you. Simple to test. I looked at it years ago but had an issue that ruled it out - can't remember what and may not be relevant these days anyway. It was bloody quick.

MX toram https://antixlinux.com/the-most-exte...on-the-planet/ &wiki
Nice laptop; 8GB ram good. Worth at least an old $10 hdd, to make it a laptop that's worth a couple hundred dollars

+1 for #13 and #14: loading the OS to RAM, that machine would fly!