Braces over and under terms in LaTeX
\underbrace and \overbrace draw a horizontal curly brace directly under or over a group of terms, with an optional label attached below (underbrace) or above (overbrace) the brace using _ or ^.
LaTeX command
\underbrace{a+b+c}_{\text{sum}}Not the symbol you meant? Draw it to find the command →
\underbrace{...}_{label} braces the group from below and puts the label under the brace; \overbrace{...}^{label} does the mirror image, bracing from above with the label on top. The label itself is ordinary maths or \text{...} content, so it can be a word, a count, or a short expression.
They're most useful for annotating a step in a derivation, marking which terms came from where, or showing that a repeated sum of n identical terms equals n times that term. Nesting is allowed, an \underbrace can sit inside another brace's content to annotate a sub-part, though it gets visually busy fast.
Since the label sits in a subscript or superscript position, wrap any words in \text{} so they print upright rather than as run-together italic letters, and keep the label short, the brace narrows towards it and long text gets cramped.
Other forms
\overbrace{...}^{...}brace aboveExamples
$\underbrace{1+1+\cdots+1}_{n \text{ times}} = n$a labelled under-brace showing repetition
$\overbrace{a+b+c}^{\text{three terms}}$a labelled over-brace
$\underbrace{x^2 + 2x + 1}_{(x+1)^2}$marking a factored form under an expression
$\overbrace{\underbrace{a}_{1} + \underbrace{b}_{2}}^{\text{total}}$a nested brace example
Tips and common mistakes
- Use _ after
\underbraceand ^ after\overbracefor the label; forgetting the underscore or caret leaves the brace unlabelled. - Wrap word labels in
\text{...}so they render upright, not as italic maths letters run together. - The label sits at a subscript or superscript position, so long labels get squeezed, keep them short.
- Nesting braces is possible but readability drops fast past two levels, consider a caption instead if you need more annotation.
\underbraceand\overbraceare built into LaTeX, so they work in any document without an extra package.
Working from handwritten notes?
LatexNotes turns a photo or PDF of handwritten mathematics into clean, compilable LaTeX - graphs and all. Free to try, no sign-up.
Convert your maths to LaTeX →FAQ
How do I add text under an underbrace?
Add _{\text{your words}} right after the closing brace of \underbrace{...}, wrapping the words in \text{} so they print upright, for example \underbrace{a+b}_{\text{sum}}.
What's the difference between \underbrace and \overbrace?
\underbrace draws the brace below the group with its label underneath, using _; \overbrace draws it above the group with its label on top, using ^.
Can I put a brace over just part of an equation?
Yes, only wrap the terms you want braced in \underbrace{...} or \overbrace{...}; the rest of the equation sits outside it as normal, for example x + \underbrace{y+z}_{\text{combine}}.
Can I nest braces?
Yes, one \underbrace or \overbrace can sit inside the content or label of another, but keep it to one or two levels, deeper nesting becomes hard to read.