<!-- Braindumps 3D print cost calculator. Paste into a Custom HTML block. Self-contained: no external files. -->
<div id="bd-pcc">
<style>
#bd-pcc{--bd-red:#d63333;--bd-line:rgba(127,127,127,.35);--bd-soft:rgba(127,127,127,.08);font:inherit;color:inherit;max-width:760px;margin:1.5em 0}
#bd-pcc *{box-sizing:border-box}
#bd-pcc [hidden]{display:none!important}
#bd-pcc fieldset{border:1px solid var(--bd-line);border-radius:10px;padding:14px 16px 6px;margin:0 0 14px}
#bd-pcc legend{font-weight:700;padding:0 6px}
#bd-pcc .row{display:grid;grid-template-columns:1fr 1fr;gap:10px 16px}
@media (max-width:560px){#bd-pcc .row{grid-template-columns:1fr}}
#bd-pcc label{display:block;font-size:.92em;margin-bottom:10px}
#bd-pcc label span.hint{display:block;opacity:.7;font-size:.88em}
#bd-pcc input,#bd-pcc select{width:100%;padding:8px 10px;margin-top:4px;border:1px solid var(--bd-line);border-radius:6px;font:inherit;background:transparent;color:inherit}
#bd-pcc select option{color:#111}
#bd-pcc .inline{display:flex;gap:8px}
#bd-pcc .inline input{flex:1;min-width:0}
#bd-pcc .inline select{width:auto;flex:0 0 auto}
#bd-pcc .check{display:flex;align-items:center;gap:8px}
#bd-pcc .check input{width:auto;margin:0}
#bd-pcc .result{border:2px solid var(--bd-red);border-radius:10px;padding:14px 16px;background:var(--bd-soft)}
#bd-pcc .total{font-size:1.6em;font-weight:700;margin:0 0 4px}
#bd-pcc table{width:100%;border-collapse:collapse;margin:8px 0}
#bd-pcc td{padding:5px 0;border-bottom:1px solid var(--bd-line)}
#bd-pcc td:last-child{text-align:right;font-variant-numeric:tabular-nums;white-space:nowrap}
#bd-pcc details{margin-top:10px}
#bd-pcc summary{cursor:pointer;font-weight:600}
#bd-pcc pre{white-space:pre-wrap;font-size:.88em;background:var(--bd-soft);padding:10px;border-radius:6px;margin:8px 0 0}
#bd-pcc .note{font-size:.85em;opacity:.75;margin-top:8px}
#bd-pcc .credit{font-size:.85em;opacity:.75;margin:10px 0 0}
</style>

<fieldset>
<legend>The print</legend>
<div class="row">
<label>Filament used
<span class="inline"><input id="bd-amount" type="number" min="0" step="0.1" value="50" inputmode="decimal" aria-describedby="bd-amount-h"><select id="bd-unit" aria-label="Unit"><option value="g">grams</option><option value="m">metres</option></select></span>
<span class="hint" id="bd-amount-h">Your slicer shows this after slicing.</span></label>
<label>Print time
<span class="inline"><input id="bd-hours" type="number" min="0" step="1" value="2" aria-label="Hours" inputmode="numeric"><input id="bd-mins" type="number" min="0" max="59" step="1" value="30" aria-label="Minutes" inputmode="numeric"></span>
<span class="hint">Hours and minutes.</span></label>
<label>Material
<select id="bd-material">
<option value="PLA" data-price="17.99" data-density="1.24">PLA</option>
<option value="PETG" data-price="17.99" data-density="1.27">PETG</option>
<option value="ABS" data-price="17.99" data-density="1.04">ABS</option>
<option value="ASA" data-price="20.99" data-density="1.07">ASA</option>
<option value="TPU" data-price="34.99" data-density="1.22">TPU 95A</option>
<option value="GLOW" data-price="22.99" data-density="1.24">Glow-in-the-dark PLA</option>
</select></label>
<label>Filament price per kg (£)
<input id="bd-price" type="number" min="0" step="0.01" value="17.99" inputmode="decimal">
<span class="hint">Typical UK price, October 2026. Change it to what you paid.</span></label>
<label>Items on the plate
<input id="bd-qty" type="number" min="1" step="1" value="1" inputmode="numeric"></label>
<label>Extra parts (£)
<input id="bd-extras" type="number" min="0" step="0.01" value="0" inputmode="decimal">
<span class="hint">Magnets, LEDs, screws, for the whole plate.</span></label>
</div>
</fieldset>

<fieldset>
<legend>The printer and electricity</legend>
<div class="row">
<label>Printer
<select id="bd-printer">
<option value="80">Bambu Lab A1 mini (80 W)</option>
<option value="95" selected>Bambu Lab A1 (95 W)</option>
<option value="105">Bambu Lab P1S or X1C (105 W)</option>
<option value="200">Bambu Lab P2S (200 W)</option>
<option value="197">Bambu Lab H2D (197 W)</option>
<option value="90">Prusa Core One (90 W)</option>
<option value="80">Prusa MK4S (80 W)</option>
<option value="249">Creality K2 Plus (249 W, measured)</option>
<option value="160">Elegoo Centauri Carbon (160 W, measured)</option>
<option value="205">Anycubic Kobra 3 (205 W, measured)</option>
<option value="custom">Other: enter the watts</option>
</select>
<span class="hint">Average while printing PLA. Hotter materials and heated chambers use more.</span></label>
<label>Average power (watts)
<input id="bd-watts" type="number" min="0" step="1" value="95" inputmode="numeric"></label>
<label>Electricity price (pence per kWh)
<input id="bd-rate" type="number" min="0" step="0.01" value="26.32" inputmode="decimal">
<span class="hint">Ofgem price cap, 1 October to 31 December 2026.</span></label>
<label>Failure allowance (%)
<input id="bd-fail" type="number" min="0" max="100" step="1" value="10" inputmode="numeric">
<span class="hint">Covers the prints that go wrong. 5 to 15% is usual.</span></label>
</div>
<label class="check"><input id="bd-wear-on" type="checkbox"> Include printer wear and tear</label>
<div class="row" id="bd-wear-row" hidden>
<label>Printer price (£)
<input id="bd-cost" type="number" min="0" step="1" value="300" inputmode="numeric"></label>
<label>Expected working life (hours)
<input id="bd-life" type="number" min="1" step="100" value="2000" inputmode="numeric">
<span class="hint">2,000 to 2,500 hours is a common rule of thumb.</span></label>
</div>
</fieldset>

<div class="result" aria-live="polite">
<p class="total" id="bd-total">£0.00</p>
<p id="bd-each"></p>
<table><tbody id="bd-lines"></tbody></table>
<details><summary>Show the working</summary><pre id="bd-working"></pre></details>
<p class="note">Electricity uses the unit rate only. The daily standing charge is paid whether or not you print, so it is not part of the cost of a print.</p>
</div>

<p class="credit">Calculator by <a href="https://braindumps.co.uk/3d-print-cost-calculator/">Braindumps.co.uk</a></p>
<script>
(function () {
  "use strict";
  /* BEGIN CALC */
  function printCost(o) {
    var grams = o.unit === "m" ? o.amount * Math.PI * Math.pow(0.0875, 2) * 100 * o.density : o.amount;
    var hours = Math.max(0, o.hours) + Math.max(0, o.minutes) / 60;
    var filament = grams / 1000 * o.pricePerKg;
    var kwh = o.watts / 1000 * hours;
    var electricity = kwh * o.ratePence / 100;
    var wear = o.wearOn && o.lifeHours > 0 ? o.printerPrice / o.lifeHours * hours : 0;
    var subtotal = filament + electricity + wear;
    var failure = subtotal * o.failurePct / 100;
    var total = subtotal + failure + o.extras;
    var qty = Math.max(1, Math.floor(o.qty));
    return { grams: grams, hours: hours, kwh: kwh, filament: filament, electricity: electricity, wear: wear, failure: failure, extras: o.extras, total: total, each: total / qty, qty: qty };
  }
  /* END CALC */

  var root = document.getElementById("bd-pcc");
  if (!root) { return; }
  function el(id) { return document.getElementById(id); }
  function num(id) { var v = parseFloat(el(id).value); return isFinite(v) && v >= 0 ? v : 0; }
  function money(v) { return "£" + v.toFixed(2); }
  function pence(v) { return v < 1 ? (v * 100).toFixed(1) + "p" : money(v); }

  function update() {
    var mat = el("bd-material").selectedOptions[0];
    var r = printCost({
      amount: num("bd-amount"), unit: el("bd-unit").value, density: parseFloat(mat.dataset.density),
      hours: num("bd-hours"), minutes: num("bd-mins"), pricePerKg: num("bd-price"),
      watts: num("bd-watts"), ratePence: num("bd-rate"), failurePct: num("bd-fail"),
      wearOn: el("bd-wear-on").checked, printerPrice: num("bd-cost"), lifeHours: num("bd-life"),
      extras: num("bd-extras"), qty: num("bd-qty") || 1
    });
    el("bd-total").textContent = money(r.total) + (r.qty > 1 ? " for the plate" : " for this print");
    el("bd-each").textContent = r.qty > 1 ? money(r.each) + " each for " + r.qty + " items" : "";
    var rows = [["Filament (" + r.grams.toFixed(1) + " g)", r.filament], ["Electricity (" + r.kwh.toFixed(4) + " kWh)", r.electricity]];
    if (el("bd-wear-on").checked) { rows.push(["Printer wear", r.wear]); }
    rows.push(["Failure allowance (" + num("bd-fail") + "%)", r.failure]);
    if (r.extras > 0) { rows.push(["Extra parts", r.extras]); }
    var body = el("bd-lines");
    body.textContent = "";
    rows.forEach(function (row) {
      var tr = document.createElement("tr");
      var a = document.createElement("td"); a.textContent = row[0];
      var b = document.createElement("td"); b.textContent = pence(row[1]);
      tr.appendChild(a); tr.appendChild(b); body.appendChild(tr);
    });
    var w = [];
    if (el("bd-unit").value === "m") {
      w.push("Grams = metres × π × 0.0875² cm² × 100 cm/m × density");
      w.push("      = " + num("bd-amount") + " × 2.405 cm³ × " + mat.dataset.density + " g/cm³ = " + r.grams.toFixed(1) + " g");
    }
    w.push("Filament    = " + r.grams.toFixed(1) + " g ÷ 1,000 × £" + num("bd-price").toFixed(2) + " = " + money(r.filament));
    w.push("Energy      = " + num("bd-watts") + " W ÷ 1,000 × " + r.hours.toFixed(2) + " h = " + r.kwh.toFixed(4) + " kWh");
    w.push("Electricity = " + r.kwh.toFixed(4) + " kWh × " + num("bd-rate") + "p = " + (r.electricity * 100).toFixed(2) + "p");
    if (el("bd-wear-on").checked) { w.push("Wear        = £" + num("bd-cost") + " ÷ " + num("bd-life") + " h × " + r.hours.toFixed(2) + " h = " + money(r.wear)); }
    w.push("Allowance   = " + num("bd-fail") + "% of the above = " + money(r.failure));
    if (r.extras > 0) { w.push("Extras      = " + money(r.extras)); }
    w.push("Total       = " + money(r.total));
    el("bd-working").textContent = w.join("\n");
  }

  el("bd-material").addEventListener("change", function () {
    el("bd-price").value = el("bd-material").selectedOptions[0].dataset.price;
    update();
  });
  el("bd-printer").addEventListener("change", function () {
    var v = el("bd-printer").value;
    if (v !== "custom") { el("bd-watts").value = v; } else { el("bd-watts").focus(); }
    update();
  });
  el("bd-wear-on").addEventListener("change", function () {
    el("bd-wear-row").hidden = !el("bd-wear-on").checked;
    update();
  });
  root.addEventListener("input", update);
  update();
})();
</script>
</div>