Writing down seed phrase: printer ink or pen ink ?

[o_e_l_e_o]

But besides metal detection, is there any other situation or reason paper may be a better choice than stainless steel?

I've discussed this before, but my main argument against stainless steel over paper is that I find it unnecessary.

When you compare a single stainless steel back up to a single paper back up, then absolutely stainless steel is a better choice. It will be more resistant to fire, water, corrosion, crush, explosions, etc. However, one back is no back up at all. You should have, at a minimum, your seed phrase backed up in two separate but secure geographical locations. Given this scenario, I find stainless steel unnecessary. What are the chances that my airgapped laptop and two separate paper back ups will all be destroyed simultaneously?

If you want to use steel then by all means go ahead, but don't let perfect be the enemy of good and don't delay backing up your seed phrase properly while you get all the necessary equipment to make a steel back up. And don't think that a single steel back up is better than redundancy with multiple paper back ups.

And if you do go for a metal back up, then please choose one which involves stamping words on to a metal plate, and not the multiple ones on the market which involve slotting tiles in to a holder, which all perform incredibly poorly on stress testing.

[LoyceV]

Purchasing an old printer from someone else is a bad, bad idea as you have no idea who and how someone may have messed with it.

Are you afraid someone might have added hidden spying technology just in case someone will print a secret on his old printer? I wouldn't worry about an old HP LaserJet (except for it's weight and size). And because they're so old and mainstream, I expect it to work without problems from most Linux LIVE DVDs.

[PawGo]

Incredible idea! To add a GSM module into old printer, change firmware and start selling it bitcoin forums. Then transmit to a given server the content of suspected prints.
Fantastic, let’s do it. How we would call our start-up?

By the way, maybe saving seed as a QRcode could be a partial solution for missing parts?

[LoyceV]

Incredible idea! To add a GSM module into old printer, change firmware and start selling it bitcoin forums. Then transmit to a given server the content of suspected prints.

Don't buy a printer on Bitcointak, buy it on Craigslist. That makes a targeted attack much less likely.

By the way, maybe saving seed as a QRcode could be a partial solution for missing parts?

Why not both? I like how a former-trusted-now-scamming paper wallet site designed the paper: print the private key twice, one of them upside down, with the QR-code in between. That means you can still recover the key even if you lose a substantial part of the paper.

[dkbit98]

Don't buy a printer on Bitcointak, buy it on Craigslist. That makes a targeted attack much less likely.

You should know that most printers have coded tracking dots that prints invisible Machine Identification Codes with time, date and printer serial number on paper, with who knows what else to track what you print.
I would never want to use something like that for printing bitcoin seed phrase, and I don't agree with you that printer ink will last for centuries.
Long time I ago I remember printing some cd covers on my old printer and they all faded a lot, this could be because of cheap ink paint, but you get my point.

[LoyceV]

You should know that most printers have coded tracking dots that prints invisible Machine Identification Codes with time, date and printer serial number on paper, with who knows what else to track what you print.

I always assumed only high-resolution "modern" printers do that, but it turns out the technology was developed in the mid-1980s. I wouldn't worry about yellow dots on an old black and white laser printer, but more imporantly: the tracking is meant to track a printout to a certain printer. Printed seed phrases aren't meant to be shared, and even if someone would get their hands on it, they wouldn't be interested to know which printer you used. They would just take your money.

Long time I ago I remember printing some cd covers on my old printer and they all faded a lot, this could be because of cheap ink paint, but you get my point.

I prefer toner over ink.

[dkbit98]

I wouldn't worry about yellow dots on an old black and white laser printer, but more imporantly: the tracking is meant to track a printout to a certain printer. Printed seed phrases aren't meant to be shared, and even if someone would get their hands on it, they wouldn't be interested to know which printer you used. They would just take your money.

I don't worry about it because I don't use printed seed words, and i don't want invisible yellow dots anywhere on my forensically traceable papers.
Using passphrase with seed words would make job harder for anyone who wants to steal your coins, but they could identify computer and printer you used, with exact details about time, date and maybe IP address.
However, there are some printer models that apparently don't display tracking dots:

Some of the documents that we previously received through FOIA suggested that all major manufacturers of color laser printers entered a secret agreement with governments to ensure that the output of those printers is forensically traceable.

https://www.eff.org/pages/list-printers-which-do-or-do-not-display-tracking-dots

I prefer toner over ink.

I prefer hand and pencil over toner.

[o_e_l_e_o]

Printed seed phrases aren't meant to be shared, and even if someone would get their hands on it, they wouldn't be interested to know which printer you used. They would just take your money.

I suppose a very theoretical risk would be an attacker finding your seed phrase and then tracking you down via this tracking information to extort you for other seed phrases, other wallets, passphrases, etc.

Just another minor point to add to the list of "Why over complicate things with a printer?". Write your seed phrase down, laminate the paper if you so choose, job done.

[PawGo]

Don't buy a printer on Bitcointak, buy it on Craigslist. That makes a targeted attack much less likely.

You should know that most printers have coded tracking dots that prints invisible Machine Identification Codes with time, date and printer serial number on paper, with who knows what else to track what you print.

If you are interested in that subject, maybe you should check that program: https://github.com/dfd-tud/deda
Developed by scientists from Dresden, allows you to detect and modify/remove yellow dots. Or just read a data encoded.

By the way, do you know story of Reality Winner? Yep, dots.

[PrimeNumber7]

I'm going to disagree with everyone above saying it doesn't really matter and instead say you should absolutely write your seed phrase by hand and not use a printer.*

Agreed. Printing a private key (or a seed phrase) increases the scope of possible ways that your key could be stolen.

I would also bring up that it is a best practice to store backups of your seed phrase in multiple mediums of storage. So if you do decide to store one copy that is written on paper, you should store another copy of your seed in some medium of storage, such as an encrypted USB stick or encrypted HDD. This way if your ink does fade, you will hopefully still have access to your other backups. 

[Kakmakr]

I will use a permanent marker on a piece of paper, where the ink can be absorbed by the paper. (Not on a piece of plastic for instance, where it will only be on the surface) ...after that, I will laminate it to protect it from the elements. (Do not place this in direct sunlight, because it will fade over time)

I will NOT print it with anything, because most printers have some kind of buffer that stores the information and this buffer can be accessed by hackers. (Photocopier machines even have hard drives that can be accessible to these hackers) ....or the buffer can be on your local PC hard drive, after it has been dumped from the Printer buffer. 

Do not place these devices on the Internet, when you do this.... I bought a cheap second hand computer and printer that will never see the Internet again ....and I use them to print "Paper wallets" for cold storage. 

[o_e_l_e_o]

I would also bring up that it is a best practice to store backups of your seed phrase in multiple mediums of storage. So if you do decide to store one copy that is written on paper, you should store another copy of your seed in some medium of storage, such as an encrypted USB stick or encrypted HDD. This way if your ink does fade, you will hopefully still have access to your other backups.

I understand the reasoning behind this, and if that makes you feel safer and/or fits with your threat model, then by all means go ahead. But again, as I discussed above regarding steel back ups, I find this unnecessary.

Lets say that I have three copies of a seed phrase, all hand written on paper (using good quality ink and good quality paper), stored in three separate physical locations. I know that under the reasonable conditions of temperature, humidity, etc., that the copy stored on site in my house will experience, I'm going to get decades out of it before the ink fades to any significant degree. In terms of my offsite back ups, I'm still checking on them at least every few months so I know if they have been compromised or damaged in any way. Even assuming these offsite backups are exposed to such environmental extremes that the ink fades in only a year, I'll find out before they become unreadable and will be able to replace then as needed.

If you have created your seed phrase on an airgapped device then there is little additional risk to creating a back up of your seed phrase on an encrypted USB drive. But very few people do this. If you have, on the other hand, created your seed phrase on a hardware wallet, which thousands if not millions more people do, then creating an encrypted USB drive back up poses a significant additional risk since most people do not have a properly airgapped device with which to do so.

[dkbit98]

Just another minor point to add to the list of "Why over complicate things with a printer?". Write your seed phrase down, laminate the paper if you so choose, job done.

Exactly, I don't see any real reason for using printers for this purpose, unless all pencils in the world are suddenly gone forever... but I guess you could still write with fingers.
I like those invisible ink pencils/pens that expose writing under specific light, and this would be my counter-attack to printer yellow dots 

If you are interested in that subject, maybe you should check that program: https://github.com/dfd-tud/deda
Developed by scientists from Dresden, allows you to detect and modify/remove yellow dots. Or just read a data encoded.

I didn't know about this, but it looks like this project is supperted by Bendestag aka German government.

I would also bring up that it is a best practice to store backups of your seed phrase in multiple mediums of storage. So if you do decide to store one copy that is written on paper, you should store another copy of your seed in some medium of storage, such as an encrypted USB stick or encrypted HDD. This way if your ink does fade, you will hopefully still have access to your other backups. 

I have several USB devices that suddenly died on me, so I am not considering them a viable option for any important backup.
They can also create errors with operating system if they are encrypted resulting in easy disc format and permanent data destruction.
I wish there was some physical switch that disables writing like it was with old magnetic tapes long time ago.

[erictan90]

Hello,

I would like to write down my seed phrase but I am hesitating between writing it on a sheet with a pen or typing it on my notepad app on my computer and print it ?
Which one will last longer ?

Thanks !

hi, you may try to memorise it and write it on a paper(offline). Never make it online!

[o_e_l_e_o]

I like those invisible ink pencils/pens that expose writing under specific light, and this would be my counter-attack to printer yellow dots 

I'm not sure what you are proposing using this invisible ink for, but it tends to fade far more quickly than regular ink so would be a poor choice for backing up your seed phrase.

I wish there was some physical switch that disables writing like it was with old magnetic tapes long time ago.

You do get USB drives with a physical write protection hardware switch. There are also WORM (write-once read-many) SD cards, which do exactly what they sound like.

hi, try to memorise it.

You can try to memorize it if you want, but only if you also have robust hand written back ups to fall back on. If you only try to memorize your seed phrase, you will almost certainly forget it at some point and lose access to your coins.

[dkbit98]

I'm not sure what you are proposing using this invisible ink for, but it tends to fade far more quickly than regular ink so would be a poor choice for backing up your seed phrase.

I don't really propose using it for anything more than maybe sending some temporary love messages, and it was more of a joke for governments using invisible yellow dots for tracking printers.

You do get USB drives with a physical write protection hardware switch. There are also WORM (write-once read-many) SD cards, which do exactly what they sound like.

They probably exist but I never saw one of this devices in my life and I never used it.
Most USB stick drives on the market don't have such option.

[larry_vw_1955]

I prefer hand and pencil over toner.

apparently pencil lasts longer than ink on paper. but nobody uses it.

[PrimeNumber7]

I would also bring up that it is a best practice to store backups of your seed phrase in multiple mediums of storage. So if you do decide to store one copy that is written on paper, you should store another copy of your seed in some medium of storage, such as an encrypted USB stick or encrypted HDD. This way if your ink does fade, you will hopefully still have access to your other backups.

I understand the reasoning behind this, and if that makes you feel safer and/or fits with your threat model, then by all means go ahead. But again, as I discussed above regarding steel back ups, I find this unnecessary.

Lets say that I have three copies of a seed phrase, all hand written on paper (using good quality ink and good quality paper), stored in three separate physical locations. I know that under the reasonable conditions of temperature, humidity, etc., that the copy stored on site in my house will experience, I'm going to get decades out of it before the ink fades to any significant degree. In terms of my offsite back ups, I'm still checking on them at least every few months so I know if they have been compromised or damaged in any way. Even assuming these offsite backups are exposed to such environmental extremes that the ink fades in only a year, I'll find out before they become unreadable and will be able to replace then as needed.

If you have created your seed phrase on an airgapped device then there is little additional risk to creating a back up of your seed phrase on an encrypted USB drive. But very few people do this. If you have, on the other hand, created your seed phrase on a hardware wallet, which thousands if not millions more people do, then creating an encrypted USB drive back up poses a significant additional risk since most people do not have a properly airgapped device with which to do so.

You make good points, but I think your points are outside of the scope of the OP's question/problem. If you are comparing storing a backup using medium A and medium B, in order to compare the two mediums, you need to assume the same security measures are taken, unless doing so would not be possible.

You do not necessarily need to use a USB stick for one of your backups, but the medium of storage for at least one of your backups should be different than your other backups. Every medium of storage has the potential for data loss under certain circumstances, and the only way to mitigate this risk is to use multiple storage mediums.

I would also point out that not all seeds are associated with cold storage. It is generally a good practice to use a seed for your hot wallet, and your hot wallet should also be backed up, including using multiple storage mediums.

I would also bring up that it is a best practice to store backups of your seed phrase in multiple mediums of storage. So if you do decide to store one copy that is written on paper, you should store another copy of your seed in some medium of storage, such as an encrypted USB stick or encrypted HDD. This way if your ink does fade, you will hopefully still have access to your other backups. 

I have several USB devices that suddenly died on me, so I am not considering them a viable option for any important backup.
They can also create errors with operating system if they are encrypted resulting in easy disc format and permanent data destruction.
I wish there was some physical switch that disables writing like it was with old magnetic tapes long time ago.

Yes, there is x problem with y medium of storage. That is why you use multiple mediums of storage so you can reduce the overall risk of losing your seed.

[o_e_l_e_o]

If you are comparing storing a backup using medium A and medium B, in order to compare the two mediums, you need to assume the same security measures are taken, unless doing so would not be possible.

If you are comparing which storage medium is more secure once they have been created, then sure, you assume they are both created securely. But in reality, that is not the case. Almost anyone can write down a seed phrase securely - just make sure you do it with nobody else around and no cameras or webcams pointed at what you are doing. Very few people on the other hand can properly create an encrypted USB drive back up from a properly airgapped computer, leaving no traces of what they have done and leaking no information in the process. This is an important point to consider.

Just as if we compare a properly created paper wallet to a properly created software wallet, then the paper wallet is exponentially more secure. However, we know from experience that many people who create paper wallets or import them later do insecurely because they far harder to create and use than a simple software wallet.

Every medium of storage has the potential for data loss under certain circumstances, and the only way to mitigate this risk is to use multiple storage mediums.

This is also mitigated by using multiple storage locations, not just mediums. If the circumstance is, for example, all my paper wallets are vulnerable to fire or water damage (which is no different to a USB drive), then I am far safer storing two paper copies in two physical locations in different states than I am storing a paper and a USB copy a few blocks from each other.

[BlackHatCoiner]

Regarding of what's better: Ink can take several decades to start fading. Pencilled material can last over a century. Even if you didn't know this, just stick with both; write your seed phrase twice, backwards and forwards. The quality of the paper should be your main concern.

As for this:

typing it on my notepad app on my computer and print it ?

I think we've over-analyzed it. It's easier and safer to avoid using a printer as it introduces additional risk for no reason.

But again, as I discussed above regarding steel back ups, I find this unnecessary.

Not only unnecessary; I personally find it worse. Metal detectors can detect those.