Pens and Pencils | Reviews and Data

Blue Ink Or Black Ink: Which One Is Best?

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Pens are sold in many different colors, but most of the time we are choosing between blue and black ink. You can’t really say one is better than the other, but they might be preferable for different application. So let’s dig into the topic a bit…

Legal Documents And Contracts

One common question we’ve encountered is people wondering if they should use blue or black ink for a legal document, like a contract, lease, mortgage, or auto loan.

While either ink is perfectly allowable, people on the receiving side of these documents (the banks, law offices etc.) recommend blue ink. This is because the documents are almost always printed and they use black ink, so the blue ink from your pen serves two important purposes:

  1. Blue ink contrasts with the black print and stands out, so it’s easy to know if you missed a signature or initial
  2. When the document is photocopied all the signatures and initials will turn black, so only the original will have blue ink on it. If you use black ink, the original document is harder to identify

For these two, rather obvious if you think about it, purposes, blue ink is preferred for most legal documents and contract signings.


What color ink should you use for an application, like for a job, credit card, or gym membership? Similar to contracts and legal documents, you’ll once again want to use blue ink.

Blue will contrast well agains the black printed ink, it’ll be highly legible on almost any light-colored paper (almost always white but sometimes yellow or pink), and it’ll let the person working with the application know which version is the original and which was photocopied.

Another surprising win for blue ink.


Choosing the right color for either signing a check or making out a check is easy: blue or black are both fine. When doing anything with check you’ll want to avoid red or any other unique or interesting colors, as the scanning machines used by the banks are generally looking for blue or black ink and something like red can set off an alert.

The much bigger issues with checks is that you want to use an ink that is water-resistant and fraud-resistant so that no one tries to wash out your signature or change the amount on the check. This is the most important when you are making out the check, but it’s worth considering for signing the check as well, especially if you aren’t immediately going to deposit it.

You should consider using a pen like the Uni-ball Sign 307 or the Zebra Sarasa, which use pigmented inks that can’t be washed out of paper.

Personal Letters

If you are writing a letter to a friend or family member, the color of ink you choose isn’t going to make or break the letter, but it’s a valid concern. Personal correspondence is an excellent opportunity to use some fun colors that are legible but aren’t something you’d use for work. This includes green, dark grey, orange, red, and purple inks. There are many different options available in each, all of which are easy to find, clear to fun, and fun to use.

But, in the context of our discussion of blue vs. black you should pick which ever you prefer. Personally I’d go with a blue ink, as there are lots of blue shades to choose from and it is a bit more interesting of a color. Also, black pens are — as mentioned in this article many times — more formal and business like, so they can come off as cold in a personal letter.


When signing a contract or printed letter you’ll once again need to choose your link color. In this case blue is preferable because it standard out versus the printed text and makes the original copy obvious, but a signature is a unique case, right? Does blue once again win out?

We did some research and more institutions are fine with blue or black. There isn’t a lot of guidance for signatures, but the US Army does specific in document AR-25 that correspondence must be printed in black and then must be signed either blue or black ink.

Tests And Exams

When it comes to writing essays for tests or big exams, you’ll want to be careful what color you use. Most teachers and professors are fine with any blue or black ink, so long as it’s a standard color that is highly legible, not a baby blue or sparkly black. Red and green colors are, of course, not allowable as they are commonly used to grade exams.

If the test does require a specific ink color, that color is almost always black, so if you want to be totally safe so ahead and use a black pen, but blue is perfectly allowable in almost all cases.

Generally the thing with an exam is that you want a comfortable pen that you can use for long periods of time without taking breaks because students tend to have to write a lot in short periods of time.

Business Appropriate

But what is more business appropriate, in a general sense: blue or black? While it’s hard to say that either inappropriate, the general understanding is that black ink is more professional feeling and blue is more casual. So if you are dealing with the sort of people that might judge your or your business on its choice of ink color then make the safe bet and choose a black ink.

For Studying

If you are trying to pick the correct in color for studying, what you actually need is the best ink for recollection of that data later on. So which color is better for memory recall?

This is a tough question to answer, but this study, called Influence of Colour on Memory Performance, looked at how colors affect memory performance and attention span. The results were interesting.

The paper says warmer colors, like red and orange, held attention the best. High color contract (such as black ink on white paper) was ideal for legibility but this didn’t correlate with better memory recall or information retention rates!

Other, less authoritative sources often tout that blue is the best color for memory retention and recall — and I’ve found the same in my life as a student — but this data isn’t compelling enough to be convince.

Ultimately we’d say that blue and black are equally good for your studies.

What About Blue-Black Ink?

Many pens, particularly fountain pen, have ink available in a very dark blue, commonly called blue-black ink. While highly legible and professional looking, we don’t take it into account here because it’s not as common as it once was and its not easy to categorize.

By way of example, if an exam calls for black ink, so you want to chance it by using blue-black ink? Definitely not… just play it safe and use the black ink. If you want to be known for your style and excellent taste then maybe blue-black is a nice middle ground — professional but also interesting — but this article is mostly focused on issues where there is correct choice and preference is not the primary concern.

Also, blue-black ink was commonly used by students in Europe, so while it might seem cool and novel in the US or other places, it can be seen as childish in other parts of the world.