ecadlib

Setup guide · DigiKey and Mouser steps walked through screen by screen, 14 November 2026

DigiKey, Mouser and Nexar keys

ecadlib can ask DigiKey, Mouser and Nexar (Octopart) who makes each part in your BOM, what it is and where its datasheet is. Each of them only answers programs that bring your own free key. This page walks you through getting each one, about five minutes per distributor.

All of this is optional. Without any key, ecadlib still builds parts from KiCad's libraries, EasyEDA/LCSC and its own standard packages, and a KiCad library works with no keys at all. A key lets ecadlib identify more parts and find their datasheets. Set up one, two or all three.

Your keys stay on your computer (encrypted for your Windows account on Windows). ecadlib sends each key only to the company it belongs to and never to us.

Where to paste a key

  1. The setup page (easiest). Run ecadlib setup or open the desktop app. Find the card Part lookups: DigiKey, Mouser, Nexar (optional), open the distributor, paste the key, press Save, then Check it works. The card shows the same steps as this page.
  2. The command line. ecadlib keys set NAME asks for the key and hides what you type. The names are under each distributor below.

Save the keys where you run ecadlib: on the setup page, or in a normal PowerShell or Command Prompt window (a normal terminal on macOS and Linux). A terminal inside an app that Windows sandboxes, such as the one in the Claude desktop app, saves to a different folder, so ecadlib run from a normal window will not see those keys. Run ecadlib keys list in the window you use: its first line names the folder it reads.

How to check it works

Press Check it works on the setup page, or run ecadlib keys check (every distributor whose keys are saved) or ecadlib keys check digikey (one of digikey, mouser, nexar). It does one real search for a common part (NE555DR), free for DigiKey and Mouser, and says in plain words whether it worked, and if not, what to fix. Nexar counts every part it returns against your allowance, so its check asks for a single result and uses one part.

DigiKey

Free. Sign up at https://developer.digikey.com.

  1. Go to developer.digikey.com and click Register / Login. New here? Click Register now and make a free account (DigiKey emails you to confirm the address). The first time, accept the API User Agreement.
  2. On Organizations, click + Create Organization. Give it a name no other DigiKey user has (for example your name plus "ecadlib") and click Add organization.
  3. Open the organization's Production Apps tab and click + Create Production App.
  4. Name the app ecadlib. OAuth Callback must be filled in and start with https: type https://localhost (ecadlib never uses it). Under Products, set Product Information V4 to ProductInformation V4 and leave the rest on None. Click Add production app. It is approved at once.
  5. Click the app's name. Its Team App Details page shows the Client ID and Client Secret (to find them again later: Organizations > your organization > Production Apps > the app). Copy them into the two DigiKey boxes on the setup page, or run ecadlib keys set DIGIKEY_CLIENT_ID and ecadlib keys set DIGIKEY_CLIENT_SECRET.

Mouser

Free, up to 30 searches a minute and 1,000 a day. Sign up at https://www.mouser.com/api-search/.

  1. Open mouser.com/api-search and click Sign Up for Search API. Sign in, or click Create a My Mouser Account first (free).
  2. Fill in the request form. Phone and Company Name are required (a hobbyist can write "Personal"; Company Type: Personal - Hobbyist, Student, Etc). Pick the Country first: the Language and Currency lists fill in after it.
  3. Application Name: ecadlib. Application Type: Internal desktop application. Estimated Userbase: 1-10 Users. Users charged: No. Advertising: No.
  4. Tick I agree to Mouser's Web API Terms of Service and click Submit Request.
  5. Mouser emails you the Search API key, usually within minutes. Keep the email: it is where you find the key again. Paste it into the Mouser box on the setup page, or run ecadlib keys set MOUSER_API_KEY.

Nexar (Octopart)

Free parts to start with; Nexar counts every part it returns, and more parts need a Nexar plan. Sign up at https://portal.nexar.com.

  1. Sign in or sign up at portal.nexar.com.
  2. Click Apps, then Create App. Tick Supply for part lookups. If you also want to send parts to Altium 365, tick Design as well: an app's scope cannot be changed later.
  3. A new app can look up 0 parts until it has a plan: click Manage supply plan and pick one. Or use the Evaluation app Nexar puts on your dashboard, which comes with free parts.
  4. Open the app and copy its Client ID and Client Secret into the two Nexar boxes on the setup page, or run ecadlib keys set NEXAR_CLIENT_ID and ecadlib keys set NEXAR_CLIENT_SECRET.

Altium 365 only. Releasing parts to an Altium 365 workspace uses the same kind of Nexar app with Design ticked, and a browser sign-in instead of a pasted key. Add the redirect address http://localhost:3000/login to the app, then press Sign in to Altium 365 on the setup page's Altium 365 card, or run ecadlib nexar signin. One app with both Supply and Design does both jobs.

If a check fails

The full guide is also in the repository: docs/part-lookup-keys.md. Something here out of date? Distributors change their sites; open an issue.