What is quoted-printable encoding?

Quoted-printable (QP) is a MIME content-transfer encoding defined in RFC 2045. It keeps printable ASCII characters as-is and encodes everything else as =XX hexadecimal sequences, making the output mostly human-readable while safe for 7-bit mail transport.

Why does = become =3D?

The equals sign = is the escape character in QP encoding. To include a literal = in the output it must be encoded as its hexadecimal byte value 3D, written as =3D.

What is the 76-character line limit?

RFC 2045 requires QP-encoded lines to be at most 76 characters long. Longer lines are split using a soft line break — a trailing = followed by CRLF — which mail agents remove when decoding.

How are Unicode characters handled?

Unicode text is first encoded as UTF-8 bytes. Each byte outside the printable ASCII range is then written as =XX. For example the euro sign € (U+20AC) becomes =E2=82=AC in UTF-8 QP encoding.

Is this the same as URL percent-encoding?

No. Both use hex escapes but QP uses = as the prefix (=XX) while URL encoding uses % (%XX). The character sets that need escaping are also different.

Quoted-Printable Encoder

Name: Quoted-Printable Encoder
Availability: InStock
Author: Nham Vu

Paste text and convert it to MIME quoted-printable encoding for use in email headers and bodies.

Plain Text Input

Use CRLF line endings (RFC 2045)

Quoted-Printable Output

Common QP Encodings

Character	Unicode	QP Encoding	Notes
=	U+003D	=3D	Escape character — must always be encoded
Space	U+0020	=20 (or space)	Trailing spaces must be encoded
Tab	U+0009	=09 (or tab)	Trailing tabs must be encoded
é	U+00E9	=C3=A9	UTF-8 bytes C3 A9
€	U+20AC	=E2=82=AC	UTF-8 bytes E2 82 AC
©	U+00A9	=C2=A9	UTF-8 bytes C2 A9

Summary

Paste text and convert it to MIME quoted-printable encoding for use in email headers and bodies.

How it works

Paste or type your plain text into the input area.
The encoder scans each character and leaves printable ASCII (33–126) as-is, except = which becomes =3D.
Non-ASCII bytes and special characters are percent-hex encoded with a leading = sign (e.g. = becomes =3D, accented letters become their UTF-8 byte sequences like =C3=A9).
Lines longer than 76 characters are folded with a soft line break (=\r\n) per RFC 2045.
The encoded output appears on the right, ready to paste into an email source.

Use cases

Encoding email bodies that contain non-ASCII characters such as accented letters
Debugging MIME messages from mail servers or email clients
Generating quoted-printable content for custom email transports
Learning how MIME encoding works for email development
Testing email client rendering of QP-encoded text
Encoding HTML email templates with special characters

Frequently Asked Questions

Last updated: 2026-06-09 · Reviewed by Nham Vu