Radian 3QX › fit in › Honda Odyssey
Will the Diono Radian 3QX fit in a 2018–2024 Honda Odyssey?
Yes — the Diono Radian 3QX fits a 2018–2024 Honda Odyssey.
The Radian 3QX is about 17" wide; the Odyssey's usable rear bench is about 55". It fits one rear position comfortably. Three even fit across the back (51" needed vs 55").
The Radian 3QX is about 17" wide; the Odyssey's usable rear bench is about 55". It fits one rear position comfortably. Three even fit across the back (51" needed vs 55").
17"Radian 3QX width
55"Odyssey rear bench
Yesthree across
★★★☆☆NHTSA Ease-of-Use
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What fits this Odyssey
- One seat, rear position: Yes. The Radian 3QX installs in an outboard rear position of a 2018–2024 Honda Odyssey with room to spare.
- Three across: Yes — three need ~51" against a ~55" bench. Test-fit; three-across is decided by half-inches.
- Modes this seat covers: rear-facing → forward-facing → booster.
- LATCH: lower anchors up to 40 lb; the Odyssey has 3 lower-anchor positions.
ℹ️ Informational only — built from NHTSA public car-seat ratings and published seat/vehicle dimensions. This is not a safety certification and not a substitute for the seat and vehicle manuals. Always confirm the fit and install yourself before every trip. The Radian 3QX's width (Diono published spec (steel-framed, 17 in)) and the Odyssey's rear-bench width (Honda dimensions + owner measurements (approx); among the best for 3-across) are both approximate — confirm with a test-fit before buying.
Common questions
Will the Diono Radian 3QX fit in a 2018–2024 Honda Odyssey?
Yes — the Diono Radian 3QX (17" wide) fits a single rear seating position in a 2018–2024 Honda Odyssey. Three of them also fit across its roughly 55" rear bench.
Can you fit three Radian 3QXs across a Odyssey?
Yes — three Radian 3QXs need about 51" and the Odyssey's usable bench is about 55". It's close, so test-fit before buying.
Sources: seat ratings & modes — NHTSA (pulled 2026-06-17); dimensions — manufacturer specs and owner measurements. Informational only — built from NHTSA public car-seat ratings and published seat/vehicle dimensions. This is not a safety certification and not a substitute for the seat and vehicle manuals. Always confirm the fit and install yourself before every trip.