ASCII Diagram Generator

Wrap text in styled ASCII boxes. Choose from simple, double-line, or rounded border styles.

Input Text

Border Style

Padding1

ASCII Box Output

Characters: 0

ASCII Diagram Generator

Wrap any text in an ASCII box frame. Choose from five border styles — single line, double line, rounded, hash, and classic ASCII plus/dash — and adjust the inner padding with a slider. Multi-line text is automatically aligned to the widest line. The output is plain text compatible with READMEs, terminal output, comments, and documentation.

Built and maintained by Meet Shah · Last updated 5 August 2026

What this tool is used for

Boxing a note or a warning inside a plain-text document.
Producing a banner for a command-line tool's output.
Framing a section header in a README that renders anywhere.
Making a callout in a log or a commit message.
Producing a diagram frame for a text-only channel.

Frequently Asked Questions

Which box-drawing characters does it use?: Unicode box-drawing for the single, double and rounded styles — `┌─┐│└┘`, `╔═╗║╚╝`, `╭╮╰╯` — and plain ASCII `+-|` for the compatibility style. The ASCII one is the fallback for anywhere the Unicode block might not render.
When should I use the ASCII style rather than Unicode?: Anywhere the output travels through something that might not be UTF-8: an old terminal, a log aggregator, a legacy ticketing system, or a source file with an unspecified encoding. Unicode boxes look far better and fail far more visibly when they fail.
Why does my diagram look ragged in a document?: Because it needs a monospace font. Box drawing depends on every character occupying exactly one cell, so a proportional font breaks the alignment immediately. In Markdown that means a fenced code block; in a document it means explicitly setting the font.
How does padding affect the box?: It adds that many spaces on each side of the content, so the border grows accordingly. The width is driven by the longest line plus padding — which is why one long line in a multi-line box stretches the whole thing rather than wrapping.
Why use ASCII diagrams at all when images exist?: Because they live in the text. They survive a diff, a code review, a `git log`, a plain-text email and a terminal — none of which render an image — and they are editable by whoever reads them next without opening a drawing tool.

Common errors and gotchas

Producing a box wider than the terminal, which wraps and breaks the frame.
Rendering in a proportional font, which destroys the alignment the box depends on.
Using box-drawing characters a target font lacks, which show as replacement glyphs.
Mixing character widths inside the box, so the right edge no longer lines up.
Putting a box around text that will be parsed by another program.