Luggage linear inches calculator

How linear inches work and which dimensions to measure

Linear measure for luggage is simply length plus width plus height of the bag as it will go through the sizer or onto the belt. Measure outer dimensions including wheels and fixed handles when that is how the airline or tour operator defines the limit; soft sides that compress are still usually quoted at their full expanded size unless the policy says otherwise. Non-positive length, width, or height is a hard error under the product contract because a zero or negative side is not a physical bag. Non-positive limit, when provided, is likewise rejected. Send required fields length, width, and height as JSON numbers or numeric strings in the same unit. Optional unit accepts in for inches (the default) or cm for centimetres; aliases units, measure_unit, and dim_unit are accepted. Aliases l, len, and depth map to length; w and breadth to width; h and ht to height. Optional limit (aliases max_linear, max, airline_limit, max_inches) is the maximum allowed linear total in that same unit—for example forty-five for a common United States carry-on linear-inch rule, or one hundred fifteen for a metric checked-bag ceiling. Magnitude caps keep arithmetic finite on the Worker isolate. Identical inputs always produce identical JSON: pure addition and a fixed inch-to-centimetre factor of two point five four, with no network, no random seed, and no wall clock.

Reading linear, dual-unit fields, and limit pass or fail

On success the response echoes length, width, height, and unit after stable rounding, plus linear equal to the sum in the input unit. linear_in and linear_cm always present the same physical size in inches and centimetres so a United States carrier page and a European packing list can share one API call. The formula field states linear equals length plus width plus height, and method is always sum_dimensions_linear_measure for stable branching in clients. When you supply limit, the response also includes within_limit and meets_limit as the same boolean, over_by as how many units the bag exceeds the ceiling when it fails, and under_by as how much headroom remains when it passes. Use linear alone for a quick total; use linear_in versus linear_cm when you need both regional displays; use the limit fields when a checkout flow or packing checklist must show pass or fail next to the airline number the traveller typed. Missing required dimensions, non-finite values, and non-positive sides all fail with invalid_input and are not charged after the engine rejects the request. This endpoint does not fetch brand-specific policies; you or your product supply the numeric limit that matches the fare rules in force.

API usage, pricing, travel workflows, and practical limits

Call the free in-browser luggage linear inches calculator for packing day, gift shopping for a new carry-on, and classroom demos of unit conversion without installing a spreadsheet. For multi-bag parties, call once per bag so each piece stays within its own class limit. Send a JSON body with length, width, height, optional unit, and optional limit (or the documented aliases). Use the prepaid API when a travel portal, baggage-fee estimator, suitcase product page, or packing app needs a stable contract under KIT balance at $0.002 per successful item; validation failures never consume balance. Pair this endpoint with weight converters or trip planners when the next question is bag weight or itinerary cost, but keep size checks here so the arithmetic stays auditable. Authors shipping SDKs can map linear, linear_in, linear_cm, and within_limit into tables that show pass or fail beside the three sides—the same shape travellers see on airline size charts at the airport counter.