{
  "schema_version": "compare-page.v2",
  "page_id": "convertible-car-seat-overhang-on-vehicle-seats-and-bases",
  "url": "https://robotrunk.com/compare/want/convertible-car-seat-overhang-on-vehicle-seats-and-bases",
  "title": "Convertible car seat overhang on vehicle seats and bases",
  "question": "Which convertible car seats extend the least past the vehicle seat or the base?",
  "answer": "Britax Poplar S: The black base runners must rest entirely flat on the vehicle seat, and up to 3 inches (7.5 cm) of the base may overhang the front in either orientation. It is 17 in (43.18 cm) wide and approximately 28.5 in (72.39 cm) long when reclined on a flat surface; installed length varies with the vehicle seat.\nBritax Poplar (anbbaby.com listing): The retailer lists overall dimensions of 20.5 × 17 × 23.5 inches and a 17-inch design width. On a flat surface, the seat is about 28.5 inches long when reclined, but installed length varies with the vehicle seat and other factors.\nBritax Poplar (Poplar listing with vehicle fit notes): The seat is 17 inches (43.18 cm) wide. It is approximately 28.5 inches (72.39 cm) long when reclined on a flat surface; vehicle geometry can change the installed measurement. Three-across worked best on full-size outboard positions beside other narrow seats or low-profile boosters. The seat failed to fit a very small Sienna centre position and had questionable side overhang in an Odyssey centre position.",
  "kind": "convertible car seat",
  "market": "US",
  "generated_at": "2026-10-21T00:34:14.165Z",
  "columns": [
    "Seat overhang",
    "Width",
    "Reclined length",
    "Vehicle side overhang"
  ],
  "notices": {
    "facts": "Every value in the table is a fact RoboTrunk checked, linked to the page it came from. A dash means no checked fact fills that cell.",
    "price": "Prices and stock change, so this page prints neither: each product name links to its RoboTrunk page, which shows them live."
  },
  "cited_facts": [
    {
      "ref": "p3.f6",
      "product": "Britax Poplar Convertible Car Seat",
      "field": "Dimensions",
      "value": "The retailer lists overall dimensions of 20.5 × 17 × 23.5 inches and a 17-inch design width.",
      "stated_as": "Dimensions:\n20.5\" L × 17\" W × 23.5\" H\nDesign Width:\n17\" (SpaceSaver™ Slim Design)",
      "source_type": "guide",
      "source_url": "https://anb-baby.myshopify.com/products/britax-poplar-convetible-car-seat",
      "source_read_at": "2026-09-24T12:41:36.289Z"
    },
    {
      "ref": "p3.f8",
      "product": "Britax Poplar Convertible Car Seat",
      "field": "Reclined length",
      "value": "On a flat surface, the seat is about 28.5 inches long when reclined, but installed length varies with the vehicle seat and other factors.",
      "stated_as": "The length is approximately 28.5 in (72.39 cm) when reclined on a flat surface, though this may vary depending on the vehicle's seat angle and other factors.",
      "source_type": "manual",
      "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
      "source_read_at": "2026-09-24T12:41:42.811Z"
    },
    {
      "ref": "p4.f4",
      "product": "Britax Poplar S",
      "field": "Dimensions",
      "value": "It is 17 in (43.18 cm) wide and approximately 28.5 in (72.39 cm) long when reclined on a flat surface; installed length varies with the vehicle seat.",
      "stated_as": "At 17 in (43.18 cm) wide, these car seats are designed to fit 3-across* in most vehicles without compromising on safety and comfort. *Britax cannot guarantee 3-across installation fitment in all vehicles.\nThe length is approximately 28.5 in (72.39 cm) when reclined on a flat surface, though this may vary depending on the vehicle's seat angle and other factors.",
      "source_type": "guide",
      "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
      "source_read_at": "2026-09-24T12:36:57.847Z"
    },
    {
      "ref": "p4.f6",
      "product": "Britax Poplar S",
      "field": "Seat overhang",
      "value": "The black base runners must rest entirely flat on the vehicle seat, and up to 3 inches (7.5 cm) of the base may overhang the front in either orientation.",
      "stated_as": "The black positioning runners on the bottom of the car seat's base must rest entirely flat on your vehicle's seat, however the space beyond the runners’ outside edges is permitted to overhang the vehicle seat edge. You are also permitted to have up to 3 inches (7.5 cm) of the base extending beyond the front edge of your vehicle's seat in either rear-facing or forward-facing modes",
      "source_type": "guide",
      "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
      "source_read_at": "2026-09-24T12:36:57.847Z"
    },
    {
      "ref": "p5.f7",
      "product": "Britax Poplar",
      "field": "Width",
      "value": "The seat is 17 inches (43.18 cm) wide.",
      "stated_as": "At 17 in (43.18 cm) wide, these car seats are designed to fit 3-across* in most vehicles without compromising on safety and comfort.",
      "source_type": "guide",
      "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
      "source_read_at": "2026-09-24T12:39:09.434Z"
    },
    {
      "ref": "p5.f10",
      "product": "Britax Poplar",
      "field": "Reclined length",
      "value": "It is approximately 28.5 inches (72.39 cm) long when reclined on a flat surface; vehicle geometry can change the installed measurement.",
      "stated_as": "The length is approximately 28.5 in (72.39 cm) when reclined on a flat surface, though this may vary depending on the vehicle's seat angle and other factors.",
      "source_type": "guide",
      "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
      "source_read_at": "2026-09-24T12:39:09.434Z"
    },
    {
      "ref": "p5.f11",
      "product": "Britax Poplar",
      "field": "Three-across fit",
      "value": "Three-across worked best on full-size outboard positions beside other narrow seats or low-profile boosters. The seat failed to fit a very small Sienna centre position and had questionable side overhang in an Odyssey centre position.",
      "stated_as": "Three-across worked best on full-size outboard positions beside other narrow seats or low-profile boosters. The seat failed to fit a very small Sienna centre position and had questionable side overhang in an Odyssey centre position.",
      "source_type": "review",
      "source_url": "https://csftl.org/britax-poplar-convertible-car-seat-review/",
      "source_read_at": "2026-09-24T12:39:12.494Z"
    }
  ],
  "rows": [
    {
      "rank": 1,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/9925193335070",
      "name": "Britax Poplar S",
      "url": "/products/ucp/anbbaby-com/9925193335070",
      "why": "The black base runners must rest entirely flat on the vehicle seat, and up to 3 inches (7.5 cm) of the base may overhang the front in either orientation.",
      "cells": [
        {
          "column": "Seat overhang",
          "fact": {
            "field": "Seat overhang",
            "value": "The black base runners must rest entirely flat on the vehicle seat, and up to 3 inches (7.5 cm) of the base may overhang the front in either orientation.",
            "stated_as": "The black positioning runners on the bottom of the car seat's base must rest entirely flat on your vehicle's seat, however the space beyond the runners’ outside edges is permitted to overhang the vehicle seat edge. You are also permitted to have up to 3 inches (7.5 cm) of the base extending beyond the front edge of your vehicle's seat in either rear-facing or forward-facing modes",
            "source_type": "guide",
            "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
            "source_read_at": "2026-09-24T12:36:57.847Z"
          }
        },
        {
          "column": "Width",
          "fact": {
            "field": "Dimensions",
            "value": "It is 17 in (43.18 cm) wide and approximately 28.5 in (72.39 cm) long when reclined on a flat surface; installed length varies with the vehicle seat.",
            "stated_as": "At 17 in (43.18 cm) wide, these car seats are designed to fit 3-across* in most vehicles without compromising on safety and comfort. *Britax cannot guarantee 3-across installation fitment in all vehicles.\nThe length is approximately 28.5 in (72.39 cm) when reclined on a flat surface, though this may vary depending on the vehicle's seat angle and other factors.",
            "source_type": "guide",
            "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
            "source_read_at": "2026-09-24T12:36:57.847Z"
          }
        },
        {
          "column": "Reclined length",
          "fact": {
            "field": "Dimensions",
            "value": "It is 17 in (43.18 cm) wide and approximately 28.5 in (72.39 cm) long when reclined on a flat surface; installed length varies with the vehicle seat.",
            "stated_as": "At 17 in (43.18 cm) wide, these car seats are designed to fit 3-across* in most vehicles without compromising on safety and comfort. *Britax cannot guarantee 3-across installation fitment in all vehicles.\nThe length is approximately 28.5 in (72.39 cm) when reclined on a flat surface, though this may vary depending on the vehicle's seat angle and other factors.",
            "source_type": "guide",
            "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
            "source_read_at": "2026-09-24T12:36:57.847Z"
          }
        },
        {
          "column": "Vehicle side overhang",
          "fact": null
        }
      ]
    },
    {
      "rank": 2,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/8833528234270",
      "name": "Britax Poplar",
      "url": "/products/ucp/anbbaby-com/8833528234270",
      "why": "The seat is 17 inches (43.18 cm) wide.",
      "cells": [
        {
          "column": "Seat overhang",
          "fact": null
        },
        {
          "column": "Width",
          "fact": {
            "field": "Width",
            "value": "The seat is 17 inches (43.18 cm) wide.",
            "stated_as": "At 17 in (43.18 cm) wide, these car seats are designed to fit 3-across* in most vehicles without compromising on safety and comfort.",
            "source_type": "guide",
            "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
            "source_read_at": "2026-09-24T12:39:09.434Z"
          }
        },
        {
          "column": "Reclined length",
          "fact": {
            "field": "Reclined length",
            "value": "It is approximately 28.5 inches (72.39 cm) long when reclined on a flat surface; vehicle geometry can change the installed measurement.",
            "stated_as": "The length is approximately 28.5 in (72.39 cm) when reclined on a flat surface, though this may vary depending on the vehicle's seat angle and other factors.",
            "source_type": "guide",
            "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
            "source_read_at": "2026-09-24T12:39:09.434Z"
          }
        },
        {
          "column": "Vehicle side overhang",
          "fact": {
            "field": "Three-across fit",
            "value": "Three-across worked best on full-size outboard positions beside other narrow seats or low-profile boosters. The seat failed to fit a very small Sienna centre position and had questionable side overhang in an Odyssey centre position.",
            "stated_as": "Three-across worked best on full-size outboard positions beside other narrow seats or low-profile boosters. The seat failed to fit a very small Sienna centre position and had questionable side overhang in an Odyssey centre position.",
            "source_type": "review",
            "source_url": "https://csftl.org/britax-poplar-convertible-car-seat-review/",
            "source_read_at": "2026-09-24T12:39:12.494Z"
          }
        }
      ]
    },
    {
      "rank": 3,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/9925032968478",
      "name": "Britax Poplar Convertible Car Seat",
      "url": "/products/ucp/anbbaby-com/9925032968478",
      "why": "The retailer lists overall dimensions of 20.5 × 17 × 23.5 inches and a 17-inch design width.",
      "cells": [
        {
          "column": "Seat overhang",
          "fact": null
        },
        {
          "column": "Width",
          "fact": {
            "field": "Dimensions",
            "value": "The retailer lists overall dimensions of 20.5 × 17 × 23.5 inches and a 17-inch design width.",
            "stated_as": "Dimensions:\n20.5\" L × 17\" W × 23.5\" H\nDesign Width:\n17\" (SpaceSaver™ Slim Design)",
            "source_type": "guide",
            "source_url": "https://anb-baby.myshopify.com/products/britax-poplar-convetible-car-seat",
            "source_read_at": "2026-09-24T12:41:36.289Z"
          }
        },
        {
          "column": "Reclined length",
          "fact": {
            "field": "Reclined length",
            "value": "On a flat surface, the seat is about 28.5 inches long when reclined, but installed length varies with the vehicle seat and other factors.",
            "stated_as": "The length is approximately 28.5 in (72.39 cm) when reclined on a flat surface, though this may vary depending on the vehicle's seat angle and other factors.",
            "source_type": "manual",
            "source_url": "https://us.britax.com/support/faq/convertible-car-seats",
            "source_read_at": "2026-09-24T12:41:42.811Z"
          }
        },
        {
          "column": "Vehicle side overhang",
          "fact": null
        }
      ]
    }
  ]
}