Spoolghetti

Check the math.

True price per kg on Amazon.com 3D printer filament searches. Best deals sorted to the top, junk filtered out.

Add to Chrome Source on GitHub
Filament search results with price per kg badges, the cheapest listing outlined in gold and the next two in green

Stop doing spool math in your head

Price per kg on everything

Packs, bundles, 4 x 1.1 kg, 250 g x 8, pounds, even listings that only show a per-ounce price.

Best deals on top

The whole search sorts cheapest per kg first. #1 gold, #2#3 green.

The whole search

More result pages load in the background, so the ranking isn't stuck on page one.

Junk filtered out

Storage boxes, dryers, spool holders, 3D pen refills, sample packs and tiny spools disappear.

Filters that stick

Material, brand and refill filters, synced across your Chrome devices.

Only when it matters

Switches on for filament searches only. Shopping for anything else, it does nothing.

Filters and dark mode

Filter panel with refill, material and brand options The same results and filter panel in dark mode

Install

Get it on the Chrome Web Store. Works in Chrome, Edge, Brave, and other Chromium browsers.

Userscript (no extension needed): install Tampermonkey or Violentmonkey, then open spoolghetti.user.js and click Install. Same features, updates itself, settings stay in that browser. Run the extension or the userscript, not both.

From source:

  1. Download the source zip and unzip it.
  2. Open chrome://extensions and turn on Developer mode.
  3. Click Load unpacked and pick the extension folder.
  4. Search Amazon.com for filament.

Firefox: the userscript should work through Tampermonkey or Violentmonkey. A native Firefox add-on is planned.

Private and free

No tracking, no analytics, no accounts, no servers. Everything runs in your browser. Read the privacy policy.

Spoolghetti is free software under the GNU GPL v3 or later: you're free to run it, study it, change it, and share it. The source is on GitHub.