Should flag
A closing paragraph of the previous block of content, sitting directly above the crowded heading with no gap at all.
Flag Crowded One
The content this heading introduces sits forty pixels away while the previous block touches the heading.
Another closing paragraph of a previous content block, again flush against the heading that follows it in the flow.
Flag Crowded Two
Second crowded case. Two or more headings must violate the principle before the rule fires on a page.
A third closing paragraph that the next heading will visually attach to, which is the inversion this rule measures.
Flag Crowded Three
Third crowded case, this time an h3, to confirm the rule reads h2 through h4 and not only the top level.
A paragraph of running prose, set with one uniform margin, so the subhead below sits as close to it as to its own text.
Flag Near Equal Under Prose
Twenty pixels above and twenty-four below, under two lines of body copy: the subhead reads as part of the run above.
Another paragraph of running prose. The subhead below keeps exactly the gap it keeps to the paragraph it introduces.
Flag Even Under Prose
Twenty-four pixels on both sides of the subhead, under body copy that runs across the column.
A closing paragraph ten pixels above a title whose module box is painted the same white as the page around it.
Flag White Module Title
The white fill shows no edge, so the paragraph above is still the title's neighbour.
A closing paragraph ten pixels above a title over a carousel that draws its slides in a shadow tree.
Flag Title Over Shadow Carousel
The next module starts well below the carousel; the title introduces the carousel, not this.
Flag Wrapped Section Title
A paragraph before a subtitle that wraps onto two lines and rests on the heading below it.
Pick a plan in one click and fly with peace of mind
Flag Two Line Subtitle
A subtitle on two lines is a block of its own, and the heading sits on it with no room.
A paragraph that closes with a short line of its own, set flat in the same box as the heading.
Read the full report on our site.
Flag Tail Line Touching
The short line closes the block above; it does not open the heading's group.
Should pass
Pass First Heading
The first heading in its case has nothing above it, so it is exempt from the rhythm comparison entirely.
A paragraph with plenty of room after it. The heading below keeps sixty-four pixels above and sixteen below.
Pass Generous Above
Sixty-four pixels above and sixteen below. The heading clearly binds to this paragraph, the healthy shape.
A short line of copy.
Pass Even Under One Line
Even spacing under a single line is not running prose: a closing line, a kicker, a caption.
A paragraph before a heading whose spacing above and below is nearly equal, with more room above than the crowded test asks.
Pass More Room Above
Twenty-four pixels above and twenty below. The heading sits closer to its own content, the healthy direction.
A paragraph before an eyebrow label. The label belongs to the heading cluster, and the cluster has room above it.
Chapter Four
Pass Eyebrow Cluster
Space is measured from the top of the cluster, where seventy-two pixels separate it from the text above.
A paragraph before an eyebrow that a site builder wrapped in its own box, with the title wrapped in another box.
Introducing
Pass Eyebrow In Wrapper
The wrapped label is still the heading's own label, and seventy-two pixels separate the pair from the text above.
A block of content that ends in a rule. The rule is the section break, so the heading below starts a section.
Pass Divider Above
Twenty-four pixels to the rule above and forty-eight to this paragraph; the rule already separates the blocks.
A block of content followed by a horizontal rule, then a heading twelve pixels under that rule.
Pass Rule Above
The measured block above is the rule itself, which separates the sections rather than crowding the heading.
Pass Accordion Question That Opens The List
Pass Accordion Question In The Middle Row
Pass Accordion Question On The Last Row
Pass Caption Under Photo
A caption set tight under its own photo belongs to that photo. The gap below leads to the card's copy.
A block of content directly above a section title that draws a rule above and below its own text.
Pass Banded Title
The title band's own rule is the separator above it, so the zero gap to the block above is not crowding.
A paragraph twenty-four pixels above a heading whose standfirst sits behind a wrapper that generates no box at all.
Pass Standfirst Behind Contents
A short standfirst twelve pixels under the heading.
A paragraph before a small card. The card boundary provides the separation for the heading inside it.
Pass Card Heading
A heading inside a small card. The rule exempts headings inside panels shorter than two hundred pixels.
A paragraph before a banded section. The heading is the first content inside a section with its own background.
Pass Band Heading
This heading is the first content inside a section that draws its own background, so the band edge separates.
A paragraph that a pull quote follows without a gap, as an article sets a quotation into its running text.
Pass Pull Quote Heading
A heading set inside a quotation is the quotation set large. It heads no section, so its spacing sets no rhythm.
Wrapper spacing
A closing paragraph above a section header whose own padding holds sixteen pixels above the title.
Flag Header Padding
The header's forty-eight pixels of bottom padding sit between the title and this, the content it introduces.
A block editor wraps every text in a box. This one is the previous block, closing its content.
Flag Block Padding
The heading block's own padding holds the spacing: sixteen above the title, forty-eight below it.
A closing paragraph above a title wrapper with a few pixels of bottom padding and a margin under it.
Flag Small Padding
Six pixels of padding and forty-two of margin still put forty-eight pixels between the title and this.
A closing paragraph above a title set beside an icon that is taller than the title's own line.
Flag Icon Beside Heading
The icon stretches the row, and the row's margin puts this content well away from the title.
A closing paragraph above a pricing title row whose button is taller than the title.
Flag Tall Button Row
View all plansThe plans the title introduces start under the whole row, fifty-eight pixels below the title.
The left column closes with a paragraph and then a title.
Flag Column Heading
The right column holds a shorter paragraph.
What the column title introduces runs under the whole row, forty-eight pixels below the title.
A closing paragraph ten pixels above a heading whose gap below is an empty spacer box.
Flag Spacer Below
The spacer holds forty-eight pixels open between the heading and this content.
A builder's flex stack puts every text in a wrapper of its own and every gap in an empty box.
Flag Stack Heading
Sixteen pixels of spacer above the title, forty-eight below it before this content.
A navy band closes a paragraph, then holds forty-eight pixels open with an empty row painted navy.
Pass Filled Spacer Row
The row is the band's own colour, so the title has forty-eight pixels above and twenty-four below.
A paragraph, then a sixteen pixel row painted a colour of its own.
Flag Divider Row
The row is a divider the title sits right under, with twenty-four pixels below it.
A band painted with a gradient, then a forty-eight pixel white strip across it.
Flag Strip Over Gradient Band
The strip is a divider the title sits right under, with twenty-four pixels below it.
A closing paragraph, then a date line in a wrapper, set like the body copy rather than as a label.
Updated March 2026
Flag Plain Line Above
The date is content of its own, so the title sits ten pixels under it and forty-eight above this.
A closing paragraph, then a code block framed on every side, twelve pixels above the next heading.
npm install impeccable npx impeccable detect src/
Flag Code Block Above
The frame is the code block's own box, not a rule, so the heading still sits closer to it than to this.
A builder puts every block in a layout row. This row closes the previous block's content.
Flag Title Alone In A Row
Feature One
The first column of the row the title introduces.
Feature Two
The second column of the row the title introduces.
A closing paragraph above a heading that ends a box drawing a rule under it.
Pass Heading Ends Ruled Box
The rule under the box ends the heading's box, so this content belongs to the next one.
A closing paragraph, then a news card whose grey section link sits a few pixels above its headline.
Pass Grey Kicker
The grey link is the headline's label, so the cluster starts at the link, twenty-four pixels under the block above.
A closing paragraph, then an italic eyebrow at body size that opens the box holding a section title.
Five screens
Pass Italic Eyebrow
The italic line is the title's label, and the cluster sits forty-eight pixels under the block above.
A closing paragraph, then a hairline eyebrow at body size that opens the box holding a section title.
Compare plans
Pass Light Eyebrow
The weight sets the line apart from the copy around it, so it is read as the title's label.
A block of tiles closes with a blue link to the full list, laid out in the same box as the tiles.
Flag Link Closing Block
The link ends the tiles above, so the title sits twelve pixels under it and forty above this.
A post excerpt closes with its grey date, and the next post's title follows twelve pixels under the date.
March 3, 2026
Flag Date Closing Post
The date belongs to the post above, so the title sits twelve pixels under it and forty above this.
A closing paragraph twelve pixels above a heading that carries a small icon as its own background image.
Flag Icon Heading
The icon decorates the heading and draws no edge above it, so the heading is measured as any other.
A closing paragraph twelve pixels above a title that draws a short accent bar under itself with a gradient.
Flag Accent Bar Heading
The bar sits under the title and draws nothing along its top, so the title is measured as any other.
A closing paragraph, then a grey sentence ten pixels above the next title, too long to read as a label.
Filed under politics and the week in review
Flag Grey Sentence Above
A sentence is content of its own whatever its colour, so the title sits ten pixels under it and forty-eight above this.
A closing paragraph directly above a band whose grey is a background image rather than a colour.
Pass Image Band Heading
The band's edge separates the title from the paragraph above, as a colour band's does.
A closing paragraph directly above a band painted with a small tiled texture instead of a colour.
Pass Tiled Band Heading
The tiled texture covers the band, and its edge separates the title from the paragraph above.
A paragraph before a subtitle set like body copy that rests on the heading it introduces.
Pick a plan in one click
Pass Touching Subtitle
The subtitle touches the heading on one line, so it is the heading's own and the gap above is the cluster's.
A paragraph before a group that opens with an eyebrow set well apart from its heading.
01 / Language and tools
Pass Distant Eyebrow
The eyebrow opens its group and sits closer to the heading than the heading sits to this paragraph.
A paragraph before a run-in heading set inline at the start of the paragraph it leads.
Pass Run In Heading
The heading starts this line of prose, so the gap below it is not a gap at all.
The next block sits forty-eight pixels below the paragraph the heading opened.