can_ada
January 28, 2026 · View on GitHub
[Fast] Python bindings for Ada, a fast and WHATWG spec-compliant URL parser. This is the URL parser used in projects like Node.js.
Installation
pip install can_ada
Binary wheels are available for most platforms. If not available, a C++17-or-greater compiler will be required to build the underlying Ada library.
WHATWG URL compliance
Unlike the standard library's urllib.parse module, this library is compliant
with the WHATWG URL specification.
import can_ada
urlstring = "https://www.GOoglé.com/./path/../path2/"
url = can_ada.parse(urlstring)
# prints www.xn--googl-fsa.com, the correctly parsed domain name according
# to WHATWG
print(url.hostname)
# prints /path2/, which is the correctly parsed pathname according to WHATWG
print(url.pathname)
import urllib.parse
urlstring = "https://www.GOoglé.com/./path/../path2/"
url = urllib.parse.urlparse(urlstring)
# prints www.googlé.com
print(url.hostname)
# prints /./path/../path2/
print(url.path)
Usage
Parsing is simple:
from can_ada import parse
url = parse("https://tkte.ch/search?q=canada")
print(url.protocol) # https:
print(url.host) # tkte.ch
print(url.pathname) # /search
print(url.search) # ?q=canada
You can also modify URLs:
from can_ada import parse
url = parse("https://tkte.ch/search?q=canada")
url.host = "google.com"
url.search = "?q=canada&safe=off"
print(url) # https://google.com/search?q=canada&safe=off
can_ada also supports the URLSearchParams API:
from can_ada import URLSearchParams
params = URLSearchParams("q=canada&safe=off")
params.append("page", "2")
params.append("page", "3")
params["q"] = "usa"
print(params) # q=usa&safe=off&page=2&page=3
print(params.has("q")) # True
print(params.get("page")) # 2
print(params.get_all("page")) # [2, 3]
print(params.keys()) # ["q", "safe", "page"]
print(params.values()) # ["usa", "off", "2", "3"]
Performance
We find that can_ada is typically ~4x faster than urllib:
------------------------------------------------------------------------------------- benchmark: 4 tests ------------------------------------------------------------------------------------
Name (time in ms) Min Max Mean StdDev Median IQR Outliers OPS Rounds Iterations
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_can_ada_parse 36.7565 (1.0) 40.3057 (1.0) 37.1606 (1.0) 0.6789 (1.0) 36.9869 (1.0) 0.2526 (1.0) 2;3 26.9102 (1.0) 27 1
test_ada_python_parse 134.0627 (3.65) 143.6443 (3.56) 135.8992 (3.66) 3.1977 (4.71) 134.7860 (3.64) 1.2441 (4.92) 1;1 7.3584 (0.27) 8 1
test_urllib_parse 208.8403 (5.68) 212.9208 (5.28) 211.2021 (5.68) 1.7273 (2.54) 211.3141 (5.71) 2.9319 (11.60) 1;0 4.7348 (0.18) 5 1
test_yarl_parse 238.6351 (6.49) 246.4206 (6.11) 242.4351 (6.52) 3.4108 (5.02) 241.8302 (6.54) 6.1566 (24.37) 2;0 4.1248 (0.15) 5 1
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
To run the benchmarks locally, use:
pytest --runslow