Rebar weight calculator

Zero or negative length or unit weight is rejected with a clear invalid_input error instead of inventing a delivery ticket from impossible quantities.

How rebar weight is computed from length and unit weight

On success the response echoes the rounded inputs, publishes total_weight and weight as the same product, formula as the string W equals L times w, message as a short English summary naming the bar size, and steps as an ordered array of substitution lines you can assert in tests or show to a client. Missing or empty bar size, non-finite numbers, and non-positive length or unit weight all fail with invalid_input so you never bill or store a hollow order line.

How to call the API and what comes back

Bar size may be a non-empty string or a finite number coerced to a short label (maximum sixty-four characters after trim). String forms of numbers are accepted when they match a strict finite numeric pattern. Prefer sending numbers for length and unit weight when you control the client; when you must send strings, avoid unit suffixes or thousand separators that would fail the finite-number pattern. Typical imperial unit weights for common US bar sizes fall roughly between about three-tenths and about thirteen pounds per foot depending on size; always use the table value that matches the grade and standard on your purchase order rather than a memorised rule of thumb. Send a JSON body with three required fields: bar_size (aliases size, designation, bar, rebar_size, bar_designation), total_length (aliases length, total_length_ft, L, linear_feet, total_ft), and unit_weight_per_foot (aliases unit_weight, weight_per_foot, plf, lb_per_ft, mass_per_length, w_per_ft). Total length and unit weight must be finite positive numbers within the published absolute range so the product remains finite in IEEE double precision on the Worker and in the browser. On success the response sets bar_size, total_length, unit_weight_per_foot, total_weight, weight, formula, message, and steps. Failed validation—missing fields, empty designation, non-finite numbers, zero or negative length or unit weight, or values outside absolute limits—returns invalid_input and is never charged. Pricing is a flat $0.002 per successful request with unit item.

Practical tips, limits, and related searches

Keep inputs inside the published absolute range so products cannot overflow into non-finite results the solver must reject. Prefer this capability when you already know the total length of a given size and the unit weight from your mill table and only need total weight; if your source is a CAD schedule, export lengths first then call once per size. Sum total length from the bar schedule by size: pieces times cut length, then add only the laps and waste your estimator requires after this call. When teaching or writing tests, pair a simple slab case using number five bars with a second unit weight to show weight scales linearly with length, and include a deliberate zero length or zero unit weight to prove the invalid_input path. This landing targets people searching for a rebar weight calculator, reinforcing bar tonnage, steel bar weight per foot, or rebar ordering weight online; it is not a rebar detailing tool, not a development-length calculator, not a concrete volume estimator, and not a structural design check for moment or shear. Failed tasks that return invalid_input do not consume prepaid balance, which keeps exploratory scripts cheap when you deliberately send a zero length to verify error handling. Round-trip checks are easy: recompute length times unit weight by hand and confirm the published total_weight matches within the same twelve-decimal rounding used for all numeric fields. Multi-size jobs are handled by calling once per bar size and summing total_weight in your own spreadsheet or estimator, so each line stays transparent for the yard ticket.