XrefBase

BOM check

Check a whole parts list at once.

Paste the part numbers from a bill of materials, with manufacturers where you have them. Every line comes back with exactly one status, and each kind of relationship keeps its own column — a mating connector is never counted as an alternative, and a part nobody has assessed is never reported as having none.

Your list

Checked and discarded. Your list is sent in the body of a request — never in a URL — looked up, and gone when the answer comes back. XrefBase does not log, cache or store it, and no account is needed.

Only the part-number and manufacturer columns leave this browser. A file you pick is read here and never uploaded. Results exist only on this page: export them before you close it.

Up to 200 part numbers per run; a repeated line counts once. A header row such as MPN, Manufacturer or Part number is recognised and skipped.

What each status means

Published replacements
The only results asserting a replacement relationship. Confirm application-specific fit before use.
Functional equivalents only
Similar function, not a confirmed drop-in. Engineering review is required before substitution. No published replacement yet.
Context only
Only same series, variants, superseded predecessors or mating counterparts — none of them a substitution claim. No published replacement yet.
In catalogue — not assessed
XrefBase carries this part with no relationships recorded yet. That means it has not been assessed — not that it has no alternative.
Not in catalogue — not assessed
XrefBase does not carry this number yet. A part absent from the catalogue has not been assessed — not cleared as having no alternative.
Manufacturer needed
More than one manufacturer's part matches this number. Choose one — there is no answer until you do.
Not found under this manufacturer
No match under the manufacturer given. The manufacturer may not be recognised — checking without it covers every manufacturer in the catalogue.
Lookup failed — not checked
XrefBase couldn't check this line. That is not an answer: retry it.

What each column claims

Published replacements Asserts substitution
The only results asserting a replacement relationship. Confirm application-specific fit before use.
Functional equivalents Not a substitute
Similar function, not a confirmed drop-in. Engineering review is required before substitution.
Superseded predecessors Not a substitute
Product history, shown for context only — not an alternative to this part.
Same series Not a substitute
Same family, different configuration. Family navigation, not a substitution claim.
Variants Not a substitute
The same part in a different keying, colour or packaging suffix.
Mating counterparts Not a substitute
What this component plugs into. These are never substitutes for it.