Scale Explorer

Space

How big is Betelgeuse?

Betelgeuse · Red supergiant in Orion

Radius (estimated)
700–1,400 solar radii 300 million–610 million mi range
Radius, recent NASA/NOIRLab estimates
700–724 solar radii 300 million–310 million mi range
Show
Human, Betelgeuse, Milky Way galaxy drawn to the same scaleHuman: height 1.61–1.75 m (too small to see at this scale). Betelgeuse: radius (estimated) 700–1,400 solar radii (too small to see at this scale). Milky Way galaxy: disc diameter (estimated) 100,000–200,000 light-years.Human: 1.61–1.75 m (too small to see at this scale)Betelgeuse: 700–1,400 solar radii (too small to see at this scale)Milky Way galaxy: 100,000–200,000 light-yearsMilky Way galaxy100,000–200,000 light-yearsHuman1.61–1.75 m · too small to seeBetelgeuse700–1,400 solar radii · too small to see

Human and Betelgeuse are too small to see at this scale and are marked with ▲.

Everything is drawn to the same scale, standing on the same ground line. Silhouettes are simplified outlines scaled to the measured dimension. A faded outline shows the top of a size range.

Compare Betelgeuse with something else →

Zoom out from an average adult to Betelgeuse

Betelgeuse is too big to show next to an average adult in one picture, so here it is in 11 steps. Each step is drawn to its own scale and zooms out from the step before.

  1. Step 1 of 11 Human → Megalodon

    A megalodon is about 8.6–15 times as long as an average adult is tall.

    Human, Megalodon drawn to the same scaleHuman: height 1.61–1.75 m. Megalodon: maximum length (estimates) 15–24.3 m.Human: 1.61–1.75 mMegalodon: 15–24.3 mMegalodon15–24.3 mHuman1.61–1.75 m
    Step 1: Human and Megalodon at the same scale.

  2. Step 2 of 11 Megalodon → Great Pyramid of Giza

    The Great Pyramid of Giza is about 5.6–9.1 times as tall as a megalodon is long.

    Megalodon, Great Pyramid of Giza drawn to the same scaleMegalodon: maximum length (estimates) 15–24.3 m. Great Pyramid of Giza: current height ≈ 137 m.Megalodon: 15–24.3 mGreat Pyramid of Giza: ≈ 137 mGreat Pyramid of Giza≈ 137 mMegalodon15–24.3 m
    Step 2: Megalodon and Great Pyramid of Giza at the same scale.

  3. Step 3 of 11 Great Pyramid of Giza → Golden Gate Bridge

    The Golden Gate Bridge is about 20 times as long as the Great Pyramid of Giza is tall.

    Great Pyramid of Giza, Golden Gate Bridge drawn to the same scaleGreat Pyramid of Giza: current height ≈ 137 m. Golden Gate Bridge: total length 2,737 m.Great Pyramid of Giza: ≈ 137 mGolden Gate Bridge: 2,737 mGolden Gate Bridge2,737 mGreat Pyramid of Giza≈ 137 m
    Step 3: Great Pyramid of Giza and Golden Gate Bridge at the same scale.

  4. Step 4 of 11 Golden Gate Bridge → Mount Everest

    Mount Everest is about 3.2 times as tall as the Golden Gate Bridge is long.

    Golden Gate Bridge, Mount Everest drawn to the same scaleGolden Gate Bridge: total length 2,737 m. Mount Everest: height above sea level 8,848.86 m.Golden Gate Bridge: 2,737 mMount Everest: 8,848.86 mMount Everest8,848.86 mGolden Gate Bridge2,737 m
    Step 4: Golden Gate Bridge and Mount Everest at the same scale.

  5. Step 5 of 11 Mount Everest → Mauna Kea

    Mauna Kea is about 1.2 times as tall as Mount Everest.

    Mount Everest, Mauna Kea drawn to the same scaleMount Everest: height above sea level 8,848.86 m. Mauna Kea: height from ocean floor to summit ≈ 10,211 m.Mount Everest: 8,848.86 mMauna Kea: ≈ 10,211 mMauna Kea≈ 10,211 mMount Everest8,848.86 m
    Step 5: Mount Everest and Mauna Kea at the same scale.

  6. Step 6 of 11 Mauna Kea → Olympus Mons

    Olympus Mons is about 2.2–2.6 times as high as Mauna Kea is tall.

    Mauna Kea, Olympus Mons drawn to the same scaleMauna Kea: height from ocean floor to summit ≈ 10,211 m. Olympus Mons: height 22–27 km.Mauna Kea: ≈ 10,211 mOlympus Mons: 22–27 kmOlympus Mons22–27 kmMauna Kea≈ 10,211 m
    Step 6: Mauna Kea and Olympus Mons at the same scale.

  7. Step 7 of 11 Olympus Mons → Mars

    Mars is about 250–310 times as wide as Olympus Mons is high.

    Olympus Mons, Mars drawn to the same scaleOlympus Mons: height 22–27 km. Mars: equatorial diameter 6,792 km.Olympus Mons: 22–27 kmMars: 6,792 kmMars6,792 kmOlympus Mons22–27 km
    Step 7: Olympus Mons and Mars at the same scale.

  8. Step 8 of 11 Mars → Uranus

    Uranus is about 7.5 times as wide as Mars.

    Mars, Uranus drawn to the same scaleMars: equatorial diameter 6,792 km. Uranus: equatorial diameter 51,118 km.Mars: 6,792 kmUranus: 51,118 kmUranus51,118 kmMars6,792 km
    Step 8: Mars and Uranus at the same scale.

  9. Step 9 of 11 Uranus → Saturn

    Saturn is about 2.4 times as wide as Uranus.

    Uranus, Saturn drawn to the same scaleUranus: equatorial diameter 51,118 km. Saturn: equatorial diameter 120,536 km.Uranus: 51,118 kmSaturn: 120,536 kmSaturn120,536 kmUranus51,118 km
    Step 9: Uranus and Saturn at the same scale.

  10. Step 10 of 11 Saturn → Sun

    The Sun is about 12 times as wide as Saturn.

    Saturn, Sun drawn to the same scaleSaturn: equatorial diameter 120,536 km. Sun: diameter ≈ 1.39 million km.Saturn: 120,536 kmSun: ≈ 1.39 million kmSun≈ 1.39 million kmSaturn120,536 km
    Step 10: Saturn and Sun at the same scale.

  11. Step 11 of 11 Sun → Betelgeuse

    Betelgeuse is about 350–700 times as in radius as the Sun is wide.

    Sun, Betelgeuse drawn to the same scaleSun: diameter ≈ 1.39 million km (too small to see at this scale). Betelgeuse: radius (estimated) 700–1,400 solar radii.Sun: ≈ 1.39 million km (too small to see at this scale)Betelgeuse: 700–1,400 solar radiiBetelgeuse700–1,400 solar radiiSun≈ 1.39 million km · too small to see
    Step 11: Sun and Betelgeuse at the same scale.

Dimensions

MeasurementMetricImperialNotesSource
Radius (estimated) 700–1,400 solar radii 300 million–610 million mi Estimated; about 700 (NOIRLab) and 724 (NASA) solar radii, and around 1,400 in the millimetre continuum seen by ALMA (ESO). Range: varies [2] [1] [3]
Radius, recent NASA/NOIRLab estimates 700–724 solar radii 300 million–310 million mi Estimated; NOIRLab 'around 700', NASA 'approximately 724' times the Sun's radius. Range: varies [2] [1]

About Betelgeuse

Betelgeuse is a red supergiant star marking the shoulder of the constellation Orion, several hundred light-years away. Its size is hard to pin down: recent NASA and NOIRLab estimates put its radius at about 700 to 724 times the Sun's, while ALMA observations of its extended atmosphere at millimetre wavelengths give around 1,400 times. Placed where the Sun is, it would swallow the orbits of the inner planets.

  • NASA estimates Betelgeuse's radius at approximately 724 times the Sun's; placed at the centre of our solar system it would swallow the orbits of Mercury, Venus, Earth and Mars. [1]
  • NASA gives an uncertain distance of roughly 548 light-years and says Betelgeuse likely started life with at least 20 times the Sun's mass. [1]
  • In 2025 the Gemini North telescope found a faint companion star, estimated at about 1.5 solar masses, orbiting within Betelgeuse's extended outer atmosphere. [2]
  • Seen by ALMA in the millimetre continuum, Betelgeuse's radius is around 1,400 times the Sun's. [3]

How many fit?

  • ≈ 280 billion–600 billion × Human · height lined up end to end match the Betelgeuse · radius (estimated)
  • ≈ 72,000–140,000 × Mars · equatorial diameter lined up end to end match the Betelgeuse · radius (estimated)

Counts divide one sourced figure by another. "End to end" uses each object's main measurement; weight and volume rows appear only when both figures are sourced.

How it compares

  • 280 billion–600 billion× Betelgeuse is about 280 billion–600 billion times as in radius as an average adult is tall. See side by side
  • 72,000–140,000× Betelgeuse is about 72,000–140,000 times as in radius as Mars is wide. See side by side
  • 38,000–76,000× Betelgeuse is about 38,000–76,000 times as in radius as Earth is wide. See side by side
  • 3,400–6,800× Betelgeuse is about 3,400–6,800 times as in radius as Jupiter is wide. See side by side
  • 4,000–8,100× Betelgeuse is about 4,000–8,100 times as in radius as Saturn is wide. See side by side
  • 350–700× Betelgeuse is about 350–700 times as in radius as the Sun is wide. See side by side

Factors compare the radius (estimated) of Betelgeuse with each object’s own main measurement (height for a human). Where a size varies, the factor is given as a range.

Notes on these figures

  • All sizes are estimated. Betelgeuse is a pulsating star with an uncertain distance and no sharp edge, so its measured size depends on wavelength and method.
  • The 1,400 solar-radius figure is for the millimetre continuum (ALMA), which sees the star's extended atmosphere; the NASA and NOIRLab estimates are about half that.
  • An older NASA APOD caption (1998) described Betelgeuse as 'over 1000 times larger' than the Sun without saying whether radius or diameter; it is listed as a source but not used for a number.
  • Sources give mass only as multiples of the Sun's mass, which the site's units do not support, so mass is left out.

Sources

  1. NASA Marshall Space Flight Center (Watch the Skies blog), Betelgeuse! Betelgeuse! Betelgeuse! Stargazers Won't See Ghosts but Supergiant Star for Spooky Season. Accessed 25 September 2026.
  2. NSF NOIRLab, Gemini North Discovers Long-Predicted Stellar Companion of Betelgeuse (noirlab2523). Accessed 25 September 2026.
  3. ESO, Betelgeuse captured by ALMA (potw1726a). Accessed 25 September 2026.
  4. NASA Science, APOD: 1998 April 19 - Betelgeuse. Accessed 25 September 2026.

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