ES
Home › Developer Tools › Quoted-Printable Encoder / Decoder

Quoted-Printable Encoder / Decoder

Decode the =3D, =20 and =C3=A9 sequences found in raw emails back into readable text, or encode text as quoted-printable for MIME messages. UTF-8 and legacy charsets, 76-character soft line breaks and RFC 2047 email headers are all supported.

Last updated:

Advertisement
Advertisement

How to use the Quoted-Printable Encoder / Decoder

  1. Choose Encode or Decode with the tabs at the top.
  2. Paste your text: plain text to encode, or the quoted-printable body of an email (the part after Content-Transfer-Encoding: quoted-printable) to decode.
  3. Pick the charset: UTF-8 for almost all modern email, or the charset named in the email's Content-Type header.
  4. Adjust options if needed: line length, CRLF or LF line endings, binary mode or email header (RFC 2047) mode.
  5. Copy or download the result, or click Swap to feed the output back in the other direction.

Quoted-printable rules (RFC 2045)

  1. Literal characters: printable ASCII from ! (33) to ~ (126) is written as is, except the equals sign.
  2. Escapes: any other byte is written as = followed by two uppercase hex digits. The equals sign itself is =3D.
  3. Spaces and tabs may appear literally, but not at the end of a line, where they become =20 or =09 (mail servers often strip trailing whitespace).
  4. Line breaks in text are kept as CRLF. In binary data they are encoded as =0D=0A.
  5. Line length: encoded lines are at most 76 characters. Longer lines are split with a soft line break: an = at the end of the line, which the decoder removes.

Non-ASCII characters are first converted to bytes using the charset (for UTF-8, é is the two bytes C3 A9) and each byte is escaped: é → =C3=A9.

Common escape sequences

SequenceMeaningSequenceMeaning
=3D==C3=A9é (UTF-8)
=20space=E9é (ISO-8859-1 / Windows-1252)
=09tab=E2=80=99’ right single quote (UTF-8)
=0D=0ACR LF line break=E2=82=AC€ euro sign (UTF-8)
= at line endsoft line break (removed)=C2=A0non-breaking space (UTF-8)

Encoded-words in email headers (RFC 2047)

Headers such as Subject and From must be ASCII, so non-ASCII text is wrapped in encoded-words: =?charset?encoding?text?=. With Q encoding, spaces become underscores and special characters use the =XX form, e.g. =?UTF-8?Q?Caf=C3=A9_menu?= is "Café menu". With B encoding the text is Base64, e.g. =?UTF-8?B?Q2Fmw6k=?= is "Café". Each encoded-word may be at most 75 characters, and whitespace between two adjacent encoded-words is ignored when decoding.

Frequently asked questions

What is quoted-printable encoding?

Quoted-printable is a MIME content transfer encoding defined in RFC 2045. It keeps printable ASCII characters as they are and writes every other byte as an equals sign followed by two hex digits, for example é in UTF-8 becomes =C3=A9. It is used for email that is mostly readable text with a few special characters.

What do =20 and =3D mean in an email?

They are quoted-printable escapes. =20 is a space (hex 20), usually one that came right before a line break, and =3D is the equals sign itself, which always has to be escaped. =0D=0A is a carriage return and line feed, and =E2=80=99 is a curly apostrophe in UTF-8.

Why do lines end with an equals sign?

An = at the very end of a line is a soft line break. Quoted-printable lines may be at most 76 characters long, so long lines are split and the trailing = tells the decoder to join them back together without adding a line break.

Quoted-printable or Base64: which should I use?

Use quoted-printable for text that is mostly ASCII, because it stays human-readable and is usually smaller. Use Base64 for binary files and for text in non-Latin scripts, where nearly every byte would need a three-character escape and quoted-printable can triple the size.

Why does my decoded text show strange characters like é?

The bytes were decoded with the wrong charset. é is what UTF-8 é looks like when read as Windows-1252. Check the charset parameter in the Content-Type header of that email part and select the same charset here.

What is the =?UTF-8?Q?…?= format in email subjects?

That is an RFC 2047 encoded-word, used to put non-ASCII text in headers like Subject and From. Q encoding is similar to quoted-printable but writes spaces as underscores. Choose the Email header mode to decode or create them; B (Base64) encoded-words are decoded too.

Are all the tools on FreeToolCabin tested for quality and accuracy?

Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.

Related tools

Base64 Encoder DecoderEncode or decode Base64 text and files, and make data URIs.URL Encoder DecoderPercent-encode or decode URLs, query strings and form data.HTML Entity Encoder / DecoderEscape and unescape HTML entities, named or numeric.Base32 Encoder / DecoderEncode and decode Base32 (RFC 4648), Base32hex, Crockford and z-base-32 from text, hex or files.Password GeneratorCreate strong passwords and passphrases.Hash GeneratorGenerate MD5, SHA-1, SHA-256 and SHA-512 hashes of text or files.MD5 Hash GeneratorGenerate MD5 hashes of text, lines or files and verify checksums.SHA-256 Hash GeneratorSHA-256 and HMAC-SHA256 hashes of text, lines or files, in hex or Base64.Bcrypt Hash Generator & CheckerCreate bcrypt password hashes and check a password against a hash.Binary TranslatorConvert text to binary, hex, octal and back.HMAC GeneratorGenerate and verify HMAC signatures with SHA-256, SHA-512, SHA-1 or MD5.CRC32 Checksum CalculatorCalculate CRC-32, CRC-32C, CRC-16 and Adler-32 checksums of text or large files.JWT DecoderDecode JSON Web Tokens, read the claims and expiry, and verify HS256 signatures.JWT GeneratorCreate and sign HS256, HS384 or HS512 JSON Web Tokens in your browser and verify them.Password Strength CheckerSee how strong a password really is, how long it takes to crack and how to improve it.Caesar CipherEncode and decode Caesar shift ciphers and crack unknown shifts with a ranked brute force.Vigenère CipherEncrypt and decrypt Vigenère and Autokey ciphers, and crack unknown keys with frequency analysis.Atbash CipherEncode and decode Atbash ciphers (A↔Z, B↔Y) in Latin or Hebrew, with a live letter mapping table.ASCII TableFull ASCII code chart 0–255 in decimal, hex, octal, binary and HTML, with search and copy.Unicode Character LookupFind Unicode characters by name or code point and copy them with UTF-8, HTML and code escapes.Punycode ConverterConvert international domain names, emails and URLs between Unicode and xn-- Punycode, in bulk.JSON Escape / UnescapeEscape text for a JSON string, unescape \n and \" back to text, or stringify a whole object.Binary to HexConvert binary to hex instantly with steps and signed mode.Hex to BinaryConvert hex to binary instantly with steps and signed mode.Binary CalculatorAdd, subtract, multiply, divide, AND, OR, XOR and shift binary numbers with decimal values.Hex CalculatorHexadecimal + − × ÷ and AND, OR, XOR, NOT, shifts with decimal and binary equivalents.Base58 Encoder / DecoderEncode and decode Base58 and Base58Check (Bitcoin alphabet) from text or hex, with checksum verification.Unicode Escape / UnescapeConvert text to \uXXXX, \u{...}, \x, &#...; or CSS escapes and decode them back.File Hash CheckerGet MD5, SHA-1, SHA-256 and SHA-512 checksums of files and verify them against a hash.TOTP GeneratorGenerate 2FA one-time codes from a secret key, create otpauth QR codes and verify codes.RSA Key GeneratorGenerate 2048, 3072 or 4096-bit RSA key pairs as PEM, PKCS#1, JWK or OpenSSH, locally.SSL Certificate DecoderDecode PEM SSL/X.509 certificates: subject, issuer, expiry, SANs, key and fingerprints.Text Encryption ToolEncrypt and decrypt text with a password using AES-256-GCM, entirely in your browser.Argon2 Hash GeneratorHash passwords with Argon2id, Argon2i or Argon2d and verify them against an encoded hash.Base64 to PDFDecode a Base64 string to a PDF with preview and download, or encode a PDF to Base64.Bitwise CalculatorCalculate AND, OR, XOR, NOT and bit shifts at 8–64 bits with a bit grid and all bases.CSR GeneratorCreate a certificate signing request (CSR) and private key with SANs, RSA or ECDSA, in your browser.MongoDB ObjectId to TimestampDecode a MongoDB ObjectId to its creation date, or build ObjectIds from dates for range queries.Base64 to FileDecode Base64 or a data URI to a downloadable file; detects the real file type and previews it.File Encryption ToolEncrypt and decrypt any file with a password using AES-256-GCM, entirely in your browser.Passphrase GeneratorMake strong, memorable diceware passphrases from a 7,776-word list, with entropy in bits.CSR DecoderDecode a PEM certificate signing request: subject, SANs, key size, signature and CA readiness checks.Enigma Machine SimulatorEncrypt and decrypt with a virtual Enigma I, M3 or M4: rotors, rings, plugboard and lampboard.Hex Opacity CalculatorConvert opacity percent to a 2-digit HEX alpha code and full #RRGGBBAA color, with a 0-100% table.Playfair CipherEncrypt and decrypt Playfair ciphers from a keyword, with the 5x5 key square and every digraph step.Pwned Password CheckerCheck if a password appeared in data breaches; only 5 characters of its SHA-1 hash are sent.RSA Encryption ToolEncrypt text with an RSA public key and decrypt it with the private key using RSA-OAEP in your browser.SAML DecoderDecode SAMLRequest and SAMLResponse messages to readable XML, attributes and validity times.SSL Certificate ConverterConvert SSL certificates and keys between PEM, DER, PFX/P12 and P7B in your browser.Checksum CalculatorCompute 8-bit sum, two's complement LRC, XOR/BCC, NMEA, Fletcher and Internet checksums of bytes.PBKDF2 Hash GeneratorDerive PBKDF2 keys from a password, salt and iteration count with SHA-1, SHA-256 or SHA-512.Protobuf DecoderDecode raw Protocol Buffers hex or Base64 without a schema, or add a .proto for field names.XML Escape / UnescapeEscape & < > " ' for XML text and attributes, unescape entities back, or wrap text in CDATA.Binary Search Tree VisualizerInsert, delete and find in BST, AVL and red-black trees with animated rotations and traversals.PGP Encrypt / DecryptEncrypt, decrypt, sign and verify PGP messages with your armored keys, entirely offline.PGP Key GeneratorGenerate an OpenPGP key pair (Curve25519, NIST ECC or RSA) with passphrase and expiry, offline.Self-Signed Certificate GeneratorCreate a self-signed SSL certificate and key for localhost or dev servers, as PEM or PFX.SHA-1 Hash GeneratorSHA-1 and HMAC-SHA1 of text or files in hex or Base64, plus Git blob hashes and verify.SHA-512 Hash GeneratorSHA-512 and SHA-384 hashes of text or files in hex or Base64, HMAC and hash verification.SRI Hash GeneratorCreate Subresource Integrity hashes (sha256/384/512) and ready <script> or <link> tags.SSH Key GeneratorGenerate Ed25519 or RSA SSH key pairs in your browser: OpenSSH public key plus private key.String Escape / UnescapeEscape or unescape strings for JavaScript, Java, C#, Python, C, SQL, regex, CSV and shell.UTF-8 Encoder / DecoderConvert text to UTF-8 bytes in hex, decimal, binary, \x or % and decode bytes back to text.UUID Decoder & ValidatorDecode any UUID: version, variant, v1/v6/v7 timestamp and MAC node, plus bulk validation.
See all 65 Encoders, Hashes & Crypto →