: Search everything on loc.gov

API: loc.gov:library-of-congress-api
Endpoint: /search/
Response format: application/json
Auth: none
Method: GET
Last Status: 0

Description

Search across all Library of Congress digital collections. Returns search results with pagination, facets, and result items.

Parameters (6)

at (string, query, optional)

Attributes to return (e.g., results, pagination, facets)

c (integer, query, optional, default: 25)

Count/items per page

fa (string, query, optional)

Facet filter for refining search results

fo (string, query, optional, default: json)

Output format

Constraints: {'enum': ['json', 'yaml']}

q (string, query, required)

Search term or query string

sp (integer, query, optional)

Start page number

Examples (6)

Search across all Library of Congress collections openapi-spec 
curl 'https://www.loc.gov/search/?q=declaration+of+independence&fo=json'
import requests

resp = requests.get(
    "https://www.loc.gov/search/",
    params={
        'q': 'declaration of independence',
        'fo': 'json',
    },
)
data = resp.json()
import zingu_apis

api = zingu_apis.api("library-of-congress")
result = api.fetch("search/", q="declaration of independence", fo="json")

for item in result:
    print(item)
const resp = await fetch("https://www.loc.gov/search/?q=declaration+of+independence&fo=json");
const data = await resp.json();
Search collections openapi-spec 
curl 'https://www.loc.gov/search/?q=cat&fo=json'
import requests

resp = requests.get(
    "https://www.loc.gov/search/",
    params={
        'q': 'cat',
        'fo': 'json',
    },
)
data = resp.json()
import zingu_apis

api = zingu_apis.api("library-of-congress")
result = api.fetch("search/", q="cat", fo="json")

for item in result:
    print(item)
const resp = await fetch("https://www.loc.gov/search/?q=cat&fo=json");
const data = await resp.json();
Search across all Library of Congress content openapi-spec 
curl 'https://www.loc.gov/search/?q=baseball&fo=json&c=25&sp=1&fa=original-format%3Abook&dates=1900%2F1950'
import requests

resp = requests.get(
    "https://www.loc.gov/search/",
    params={
        'q': 'baseball',
        'fo': 'json',
        'c': '25',
        'sp': '1',
        'fa': 'original-format:book',
        'dates': '1900/1950',
    },
)
data = resp.json()
import zingu_apis

api = zingu_apis.api("library-of-congress")
result = api.fetch("search/", q="baseball", fo="json", c=25, sp=1, fa="original-format:book", dates="1900/1950")

for item in result:
    print(item)
const resp = await fetch("https://www.loc.gov/search/?q=baseball&fo=json&c=25&sp=1&fa=original-format%3Abook&dates=1900%2F1950");
const data = await resp.json();
Search across Library of Congress collections openapi-spec 
curl 'https://www.loc.gov/search/?fo=json&q=declaration+of+independence&c=25&sp=1&fa=original-format%3Abook&all=True&sb=relevance&dates=1776-1800'
import requests

resp = requests.get(
    "https://www.loc.gov/search/",
    params={
        'fo': 'json',
        'q': 'declaration of independence',
        'c': '25',
        'sp': '1',
        'fa': 'original-format:book',
        'all': 'True',
        'sb': 'relevance',
        'dates': '1776-1800',
    },
)
data = resp.json()
import zingu_apis

api = zingu_apis.api("library-of-congress")
result = api.fetch("search/", fo="json", q="declaration of independence", c=25, sp=1, fa="original-format:book", all="True", sb="relevance", dates="1776-1800")

for item in result:
    print(item)
const resp = await fetch("https://www.loc.gov/search/?fo=json&q=declaration+of+independence&c=25&sp=1&fa=original-format%3Abook&all=True&sb=relevance&dates=1776-1800");
const data = await resp.json();
Search across Library of Congress collections probe-gate 
curl 'https://www.loc.gov/search/?fo=json&q=declaration+of+independence&c=25&sp=1&fa=original-format%3Abook&all=True&sb=relevance&dates=1776-1800'
import requests

resp = requests.get(
    "https://www.loc.gov/search/",
    params={
        'fo': 'json',
        'q': 'declaration of independence',
        'c': '25',
        'sp': '1',
        'fa': 'original-format:book',
        'all': 'True',
        'sb': 'relevance',
        'dates': '1776-1800',
    },
)
data = resp.json()
import zingu_apis

api = zingu_apis.api("library-of-congress")
result = api.fetch("search/", fo="json", q="declaration of independence", c=25, sp=1, fa="original-format:book", all="True", sb="relevance", dates="1776-1800")

for item in result:
    print(item)
const resp = await fetch("https://www.loc.gov/search/?fo=json&q=declaration+of+independence&c=25&sp=1&fa=original-format%3Abook&all=True&sb=relevance&dates=1776-1800");
const data = await resp.json();
Search everything on loc.gov probe-gate 
curl 'https://www.loc.gov/search/?fo=json&c=25'
import requests

resp = requests.get(
    "https://www.loc.gov/search/",
    params={
        'fo': 'json',
        'c': '25',
    },
)
data = resp.json()
import zingu_apis

api = zingu_apis.api("library-of-congress")
result = api.fetch("search/", fo="json", c=25)

for item in result:
    print(item)
const resp = await fetch("https://www.loc.gov/search/?fo=json&c=25");
const data = await resp.json();

Probe History

Latency

Status Codes

TimeStatusLatencySize
2026-04-16 17:50:15.353800 ERR —
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