The Internet Routing Registries are databases where operators record what they intend to announce and who may announce it, as RPSL objects: route and route6 objects for prefixes, as-sets for groups of ASes, aut-nums for the ASes themselves and mntners for the handles that maintain them. Most prefix filters between networks are still built from this data.

Why does the same prefix appear more than once?

Because the IRR is not one database. The same prefix is routinely registered in several registries, sometimes with different origin ASes, and objects nobody has cleaned up outlive the arrangements that justified them. NoToolkit shows every registry's copy separately rather than picking a winner, because which registry an object came from is part of the answer.

Yes. GET https://notoolkit.com/?irr=193.0.0.0/21 returns JSON, and the same endpoint takes an AS number, an as-set name or a maintainer handle. No API key and no sign-up.

Every mirrored registry at once · refreshed 4-hourly

IRR Validator

Q: What does expanding an as-set do?

An as-set lists members, and those members are often other as-sets, which is how customer cones are written. Expanding one follows the nesting all the way down and returns the flat list of AS numbers a prefix filter built from that set would ultimately let in — the question you actually have when someone hands you an as-set.

Q: How current is the data?

Each registry's published database dump is re-imported every four hours, and most registries regenerate those dumps once a day. The page shows when each registry was last loaded. This is a mirror of the dumps, not a live whois session, so an object registered in the last few minutes may not be here yet.

NOC Operator Toolkit

Route objects, as-sets, aut-nums and maintainers across every routing registry we mirror, searched together. Free. No API key. No rate limits (be reasonable).

Live Demo

Look something up

A prefix, an AS number, an as-set, a route-set or a maintainer handle. It works out which you meant.

4,656,923 route objects across 16 registries·oldest refreshed 5h 7m ago

Examples: 193.0.0.0/21 AS3333 AS-RIPENCC 8.8.8.0/24 RIPE-NCC-MNT

Enter a prefix, AS, as-set or maintainer above and click Look up.

Registries

What is mirrored

Each registry’s published database dump, re-imported every four hours. A registry whose import fails keeps the objects it already had rather than disappearing.

APNIC

886,449 route · 1,057,229 route6

5,866 sets · 26,077 aut-nums

Updated 4h 32m ago

RADB

1,130,544 route · 216,022 route6

19,013 sets · 10,080 aut-nums

Updated 5h 4m ago

RIPE

469,582 route · 112,599 route6

31,238 sets · 39,899 aut-nums

Updated 5h 7m ago

NTTCOM

281,263 route · 6,112 route6

906 sets · 575 aut-nums

Updated 22m 52s ago

ARIN

151,968 route · 46,263 route6

9,155 sets · 4,325 aut-nums

Updated 4h 23m ago

AFRINIC

122,552 route · 5,128 route6

1,672 sets · 2,793 aut-nums

Updated 5h 5m ago

32,976 route · 16,005 route6

16,573 sets · 5,312 aut-nums

Updated 5h 4m ago

ALTDB

28,263 route · 8,064 route6

2,441 sets · 2,042 aut-nums

Updated 5h 4m ago

BELL

29,364 route · 94 route6

51 sets · 108 aut-nums

Updated 5h 4m ago

LACNIC

14,939 route · 5,251 route6

2,416 sets · 2,995 aut-nums

Updated 23m 12s ago

REACH

16,738 route · 1,284 route6

5 sets · 2 aut-nums

Updated 5h 4m ago

JPIRR

14,243 route · 1,383 route6

356 sets · 487 aut-nums

Updated 5h 4m ago

CANARIE

1,218 route · 81 route6

123 sets · 177 aut-nums

Updated 5h 4m ago

BBOI

1,141 route · 157 route6

46 sets · 70 aut-nums

Updated 5h 4m ago

PANIX

8 route · 1 route6

4 sets · 1 aut-nums

Updated 5h 4m ago

NESTEGG

2 route · 0 route6

0 sets · 2 aut-nums

Updated 5h 4m ago

Reference

API Documentation

No authentication required. CORS headers are included on all responses.

GET/?irr={query}

Look a prefix, AS number, as-set, route-set or maintainer handle up across every mirrored registry. The response’s kind field says which of those the input was taken to be, and the rest of the body depends on it.

Parameter	Type	Description
irr	string	A prefix (`193.0.0.0/21`), a bare address, an AS number (`AS3333`), a set name (`AS-RIPENCC`, `RS-EXAMPLE`, `AS3333:AS-CUSTOMERS`) or a maintainer handle.

# what is registered for a prefix, and by whom
curl -s "https://notoolkit.com/?irr=193.0.0.0/21" | jq .

# every route object an AS has registered
curl -s "https://notoolkit.com/?irr=AS3333" | jq '.route_objects'

# expand an as-set to the prefix list a filter from it would hold
curl -s "https://notoolkit.com/?irr=AS-RIPENCC" | jq -r '.prefixes.ipv4[]'

# or just the member ASes
curl -s "https://notoolkit.com/?irr=AS-RIPENCC" | jq '.expanded_asns'

# everything one maintainer is listed on
curl -s "https://notoolkit.com/?irr=RIPE-NCC-MNT" | jq .

POST/

The same lookup with a JSON body.

curl -s -X POST https://notoolkit.com/ \
  -H 'Content-Type: application/json' \
  -d '{"irr":"AS-RIPENCC"}' | jq .

GETResponse fields

Field	Description
kind	`prefix`, `asn`, `set`, `mntner` or `text` — how the input was read.
sources	The registries that contributed to this answer.
exact_objects	`kind=prefix`: route objects for exactly this prefix, each with its origin AS, registry, description and maintainers.
covering_objects	`kind=prefix`: route objects for less specifics that cover it. A prefix with none of its own may still be covered by one of these.
registered_origins	`kind=prefix`: the origin ASes registered for the exact prefix — what a filter built from the IRR would permit.
route_objects	`kind=asn`: every prefix registered with this AS as its origin. `route_count` is the true total when the list is truncated.
expanded_asns	`kind=set`: the flat list of AS numbers the set resolves to, following nested sets across every registry.
prefixes	`kind=set`: the prefix list a filter built from the set would hold, deduplicated across registries and split into `ipv4` and `ipv6`. `prefix_count` gives the per-family totals and `prefix_total` the sum; `prefixes_truncated` says whether the cone ran past the response ceiling.
member_of	`kind=set`: the sets that name this one as a member.

FAQ

Common Questions

What is the IRR?

A set of databases where operators record what they intend to announce and who may announce it, as RPSL objects: route and route6 for prefixes, as-set for groups of ASes, aut-num for the ASes themselves, and mntner for the handles that maintain them. Most of the prefix filters between networks are still generated from this data, which is why a missing or wrong object shows up as “my route isn’t propagating”.

Why is the same prefix registered twice?

Because the IRR is not one database. The same prefix is routinely registered in several registries, occasionally with different origin ASes, and objects nobody cleaned up outlive the arrangements that justified them. Nothing here picks a winner: every registry’s copy is shown with the registry it came from, because that is part of the answer. A prefix registered in one registry with the right origin and in another with an old one will pass some networks’ filters and fail others.

What does expanding an as-set do?

An as-set lists members, and those members are usually other as-sets — that nesting is how customer cones are written. Expanding one follows it all the way down to the member AS numbers, then takes the second step to the prefix list those ASes have route objects for — the same thing bgpq4 produces, and the thing you actually need when a customer hands you an as-set. Members are followed across registries, because a set defined in RADB routinely names one that only exists in RIPE.

How does this relate to RPKI?

They answer the same question with different authority. A ROA is cryptographically signed and traces to an RIR trust anchor; an IRR route object is an ordinary database record, as trustworthy as the registry it sits in and whoever last touched it. In practice you need both — filters are still built from the IRR, and RPKI is what catches the cases where the IRR is wrong. The looking glass shows both for every path.

How current is the data?

Each registry’s published dump is re-imported every four hours, and most registries regenerate those dumps daily. The cards above say when each one was last loaded. This is a mirror of the dumps rather than a live whois session, so an object created in the last few minutes will not be here yet.

Is there an API?

Yes — see the documentation above. GET /?irr=193.0.0.0/21 returns JSON, and the same endpoint takes an AS number, a set name or a maintainer handle. No key, no sign-up.