What does plaintext mean?
Plaintext is ordinary, unencoded text that is immediately readable, as well as digital text presented without formatting or markup. In discussions of computer security, the word contrasts with ciphertext: plaintext can be intercepted and understood directly, whereas ciphertext requires a key or other means of decryption. This makes the expression especially important in warnings about passwords, personal information, financial records, and electronic messages. A plaintext file may contain only characters such as letters, numbers, and spaces, without the instructions and tags used to specify fonts, colours, layouts, or other visual features. The term can consequently describe both the absence of encryption and the absence of rich formatting. In professional and technical contexts, it signals a security condition or a deliberately simple data format. It is more precise than simply saying that information is “in the clear,” while the separate term “plain text” remains common in general computing and publishing contexts.
Text that is unencrypted and can be read without a key or decoding program; also, text containing no formatting or markup.
"Never send sensitive information as plaintext over an unsecured network."
The security sense is especially common in technical writing. As a file format, the term is also frequently written as “plain text.”
Denoting text or a file that is unencrypted, unformatted, or represented without rich markup.
"The developer exported the configuration as a plaintext document."
This attributive use is often written “plain-text” when it appears before a noun, as in “plain-text file.”
The word is normally treated as a mass noun when referring to unencrypted material; the plural is uncommon and is more likely in references to separate plaintext documents or representations.
"The two plaintexts contain the same account names but different identifiers."
A ciphertext may resemble nonsense, but plaintext tells its story to anyone who can see it.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does plaintext come from?
Plaintext is a compound of “plain” and “text.” “Plain” entered Middle English from Anglo-Norman French plein, ultimately derived from Latin plenus, meaning “full” or “level.” “Text” comes through French from Latin textus, a word associated with texere, “to weave,” and with the presentation of written words. The modern compound acquired its computing sense through the contrast between readable information and encoded or encrypted information.
How plaintext is actually used
In computing, plaintext is often used in discussions of encryption, authentication, and data security. The term is sometimes hyphenated when used attributively, especially in compound nouns such as “plain-text file.”
Easily confused with plaintext
Plaintext is readable as written, whereas ciphertext has been transformed into an encoded form that requires a key to decipher.
Plaintext contains no formatting or markup, while rich text can preserve styles, fonts, images, and other formatting.