Thieves Cant in 5e: What Is It & How It Works

Welcome to our guide to thieves’ cant, a unique way of communicating that hides in plain sight like a rogue passes unnoticed through a crowd. 

In this article, we’re going to be taking a look at the origins of thieves’ cant, how it works, and how to use it the next time you’re playing a rogue. 

A black-clad thief stops to study a chalk mark on the wall. It’s barely noticeable, unremarkable to the untrained eye, but it tells her everything she needs to know. 

The people who live here have guards on patrol. With dogs. But, they are also very wealthy, and their hired goons don’t patrol inside the sprawling townhouse at night. 

Grinning, the thief settles into the shadows across the street where she can watch the pattern of patrols unseen and plan the perfect time to strike.

A light rain starts to fall on the street, the townhouse, and the hood of the thief’s robe. By the time it stops, the small chalk mark will be washed away. 

What Is Thieves’ Cant? 

Thieves’ cant is the secret language of rogues, thieves, beggars, and assassins.

Much like druidic, it’s almost exclusively used as a secondary, secret form of communication by a particular class of people — in this case rogues — without giving anything away to outsiders.

Where theives’ cant differs from druidic – and just about every other language in D&D, almost to the point of it not being a language at all – is that you can’t just speak thieves’ cant. 

Thieves’ Cant 

During your rogue training, you learned thieves’ cant, a secret mix of dialect, jargon, and code that allows you to hide messages in seemingly normal conversation.

Only another creature that knows thieves’ cant understands such messages. It takes four times longer to convey such a message than it does to speak the same idea plainly.

In addition, you understand a set of secret signs and symbols used to convey short, simple messages, such as whether an area is dangerous or the territory of a thieves’ guild, whether loot is nearby, or whether the people in an area are easy marks or will provide a safe house for thieves on the run.

Player’s Handbook 

Thieves’ Cant as ASL (Atreides Battle Language)

The closest thing I’ve seen to thieves’ cant in fiction is in Dune by Frank Herbert. 

Several of the Great Houses and the Bene Gesserit sisterhood use an array of secret hand sign languages — also relying on minute body language cues and modulations in tone of voice — that allow people fluent in them to have entire conversations with one another while, on the face of it, they’re talking about something (or even to someone) completely different. 

Likewise, two people fluent in thieves’ cant can share ideas and information with one another by dropping fragments of slang, code, hand gestures, and other subtle clues into conversation.

IIt’s all about disguising your true message within a harmless one — not through double meanings and subtext, but by layering in subtle sleight of hand and innocuous gestures that actually tell the real story. 

However, the actual conversation on the surface of things takes longer than regular speech, and it can’t express complex ideas very efficiently.

It takes four times as long to “say” something in thieves’ cant as in common, so you’re probably going to be using it to flash one- or two-word phrases like “RUN,” “DANGER,” “NOW,” and so on.

Thieves’ Cant at the Table 

One of the coolest things about thieves’ cant is the fact you can effectively carry on two conversations at once. Obviously, roleplaying this can be tricky. 

My favorite way I’ve seen a dungeon master run this at the table was to require the characters communicating in thieves’ cant to send each other messages using their phones, but they were only allowed to type while they were talking in character

It was honestly really entertaining to listen to the DM and rogue player say stuff like, “Yes, I hear the weather is… uh.. I do like steak.. In the… sorry what were we talking about?” as they furiously mashed buttons under the table.

They got the hang of it in the end though. 

Also, while the surface conversation isn’t the point, thieves’ cant still needs the conversation to take place in a shared language to work.

Because cant is largely made up of repurposed words from the shared language, someone who just speaks common and thieves’ cant probably couldn’t communicate with someone who only speaks sylvan and thieves’ cant, for example. 

The other way to think about thieves’ cant is as an impenetrable slang.

This is actually probably the closest iteration to the language’s historical origin as a cryptolect or argot in England and other English speaking countries as far back as the 1500s. 

(It’s not just an English phenomenon either; thieves’ cant’s South German and Swiss equivalent is the Rotwelsch, its Dutch equivalent is Bargoens, the Serbo-Croatian equivalent is Šatrovački, and the Polish equivalent is Grypsera.)

The language was used by beggars, thieves, highwaymen, and other folk who wanted to evade detection or being overheard. Basically, it’s a whole load of impenetrable slang.

Some of the terminology used in older real-world thieves’ cant has even made its way into modern language as well. 

The word “fence” to mean someone who sells stolen goods is from thieves’ cant — as is the practice of referring to cops as pigs. 

I think a nice touch in your game would be to have people who don’t necessarily speak or understand thieves’ cant pepper their speech with the odd word or phrase, in much the same way I say things like “tubular” and “finna” when I’m hanging out with anyone under the age of 25. 

Language All Its Own 

Thieves’ cant has taken on a lot of different shapes over the years.

If you’re interested in making it into a more discrete, separate language from common or other racial linguistic systems, then there’s an exhaustive primer with notes on pronunciation and translation along with a printable pocket thieves’ cant dictionary here in Issue #66 of Dragon Magazine (page 35). 

In its written form, thieves’ cant is much closer to an actual language — albeit a rather simple one more akin to reading road signs or ancient pictographs.

Much like spoken thieves’ cant, these symbols prize anonymity over eloquence and are once again used to convey simple concepts, usually about the location in which they’re found. 

A particular sign scrawled on a wall might mark a particular bar as a place that’s hostile to thieves, for example.

A thieves’ guild hiding in plain sight may even incorporate a piece of thieves’ cant into the signage of their “legitimate” business.

Or a crime boss might carve the thieves’ cant symbol for “TRAITOR” into the chest of an underling that crossed them. 

In terms of real world inspiration for thieves’ cant, the written form and function probably bears closest resemblance to Depression-Era Hobo Slang.

It’s easy to see how, with just a little tweaking, you could turn this into something that makes perfect sense in a fantasy campaign. 

For even more or an exploration of thieves’ cant and how to think about using it, there’s an amazing video by Dael Kingsmill over at Monarch’s Forge that tackles the subject in greater detail. 

Before we wrap up, however, let’s have a think about some of the potential applications (both rooted in historical uses for the languages that inspired or are similar to thieves’ cant) and some of the implications of using that language in a fantasy world. 

How Can I Use Thieves’ Cant? 

To recap, if you know thieves’ cant, you can… 

  1. Communicate with someone by hiding messages inside an otherwise innocent conversation. 
  2. Leave written messages that hide in plain sight to impart useful information to other thieves 

With that in mind, there are a bunch of cool ways to use thieves’ cant, from coordinating a large network of informants and thieves to finding your feet in the criminal underworld after moving to a new city. 

You could use it to hide a threat, or a warning, or a message of support — any time you want to get something across to another thief without tipping off curious onlookers, thieves’ cant is the way to go. 

Likewise, if there are multiple rogues in your party, having a secret language used to coordinate plans while you all pretend to listen to the BBEG monologue can be super useful.

Even if you’re the only rogue in the party, there’s nothing to stop you spending downtime to teach your fellow party members to recognize the codes for “GET HIM” and “RUN AWAY.” 

Just remember, however you decide to tackle thieves’ cant in your world, that it’s a language that’s dependent on hiding within another language or somewhere else it won’t be noticed — like a rogue blending into the crowd.