Closer to the smallest thing — or the biggest?
Line up a quark, a grain of rice and a galaxy on one logarithmic ruler spanning 62 orders of magnitude, from the Planck length to the observable universe. A 1.7 m human sits at 57% — nearer the biggest end than the smallest.
Size s
Planckdrag to any size, or try a preset belowUniverse
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The Planck length isn't the size of a real object — it's the theoretical scale at which our current physics stops making sense, used here only as one possible small-end reference. The observable universe's diameter is about 93 billion light-years. Every point is placed by its order of magnitude, i.e. its base‑10 logarithm: equal steps are equal multiples, not equal distances. The quark mark is an upper limit, not a measured diameter: CMS has probed for quark substructure down to 10−20 m without finding it. The weak force’s reach is about 10−18 m. The Oort Cloud is a hypothesized shell around the Sun; its outer edge may reach 1.6 light-years away, so this ruler uses a rough 3.2-light-year diameter. See CERN’s explanations of the quark limit and the weak force’s range, NASA’s Oort Cloud summary, plus the classic orders of magnitude (length) table.
Largest exoplanetNASA’s catalogue lists V2376 Ori b at 87.21 Earth radii: about 1.11 million km across. Its estimated mass is 20 Jupiters, so the classification sits near the planet/brown-dwarf boundary. NASA Exoplanet Archive
Largest starStephenson 2-18 is often cited at about 2,150 solar radii, or roughly 3.0 billion km across. That extreme estimate depends on an uncertain distance, so treat it as provisional. Estimate and uncertainty
Largest black holeTON 618 is the most massive observed black hole in this comparison: its estimated event-horizon diameter is about 390 billion km. Current record summary
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