Size It Up

ALL ANSWERS · DINOSAURS · DAILY No. 18 · SEPTEMBER 21, 2026

Size It Up Dinosaurs answer: September 21

The five Dinosaurs silhouettes for September 21, with the true sizes. If you have not played yet, this page is a spoiler — play these five first, then come back to argue with the numbers.

Day 18 ran from an oviraptor (2 m) to an apatosaurus (21 m). The widest gap was round 5, Apatosaurus against Anchiceratops, at 3.5×; the closest call was round 2, Plateosaurus against Concavenator, only 1.2× apart — the kind of round that separates a 90 from a 60.

  1. ROUND 1

    Alioramus Alioramus remotus vs Triceratops Triceratops horridus

    Triceratops · reference · 9 m
    Alioramus · true length · 6 m

    1.5× shorter than the triceratops

    Alioramus is represented here by a selected estimated total length of 6 m. Dinosaur reconstructions vary; this is the published estimate used for this comparison.

  2. ROUND 2

    Plateosaurus Plateosaurus vs Concavenator Concavenator corcovatus

    Concavenator · reference · 6 m
    Plateosaurus · true length · 7 m

    1.2× longer than the concavenator

    Plateosaurus is represented here by a selected estimated total length of 7 m. Dinosaur reconstructions vary; this is the published estimate used for this comparison.

  3. ROUND 3

    Oviraptor Oviraptor philoceratops vs Europasaurus Europasaurus holgeri

    Europasaurus · reference · 6.2 m
    Oviraptor · true length · 2 m

    3.1× shorter than the europasaurus

    Oviraptor is represented here by a selected estimated total length of 2 m. Dinosaur reconstructions vary; this is the published estimate used for this comparison.

  4. ROUND 4

    Zuniceratops Zuniceratops christopheri vs Allosaurus Allosaurus fragilis

    Allosaurus · reference · 9.7 m
    Zuniceratops · true length · 3.5 m

    2.8× shorter than the allosaurus

    Zuniceratops is represented here by a selected estimated total length of 3.5 m. Dinosaur reconstructions vary; this is the published estimate used for this comparison.

  5. ROUND 5

    Apatosaurus Apatosaurus louisae vs Anchiceratops Anchiceratops ornatus

    Anchiceratops · reference · 6 m
    Apatosaurus · true length · 21 m

    3.5× longer than the anchiceratops

    Apatosaurus is represented here by a selected estimated total length of 21 m. Dinosaur reconstructions vary; this is the source value used for this comparison.

Beat these tomorrow

Every round is worth up to 100 points: within 6% of the true size scores 100, half or double scores 45, five times off scores zero. The daily puzzle is the same five for everyone and refreshes at midnight in your time zone; if you want more than five, Size It Up Unlimited draws fresh pairs from the whole library for as long as you like.

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