google-flights-search 0.1.3

Zero-browser Google Flights SSR client that correctly handles small/regional airports by fixing protobuf URL encoding.

Google Flights Search

繁體中文 | English

A lightweight Google Flights SSR client that actually works for small and regional airports — no browser, no Playwright, no Google account needed.

Why gf-search instead of fast-flights?

Existing libraries like fast-flights silently return empty results for low-traffic airports (e.g. Taichung RMQ, Kumamoto KMJ). The root cause is an incomplete protobuf URL encoding: Google receives a malformed request and skips on-demand calculation, returning data[3] = null.

gf-search reverse-engineered the exact protobuf format Chrome sends, with three critical fixes:

Field	fast-flights	gf-search
Airport.field_1 (entity type)	missing	1 = IATA airport, 2 = city entity ID
Info.field_1, Info.field_2	missing	28, 2 (query type flags)
Info.field_16	missing	INT64_MAX — triggers on-demand calculation for small airports

Result: RMQ → KMJ returns full flight data including Starlux Airlines (JX) direct flights, whereas fast-flights returns data[3] = null.

Installation

pip install google-flights-search

Or for local/editable development:

git clone https://github.com/NYCU-Chung/google-flights-search
cd gf-search
pip install -e .

Quick Start

from gf_search import search

# Search flights from Taoyuan (TPE) to Tokyo Narita (NRT)
results = search("TPE", "NRT", "2026-08-08")
for r in results:
    print(r["airlines"], r["price"], r["stops"], "stop(s)")

# Small airport example — this is where gf-search shines
# fast-flights returns nothing; gf-search returns Starlux JX direct flights
results = search("RMQ", "KMJ", "2026-08-08")
for r in results:
    print(r["airlines"], r["price"])

API Reference

search()

from gf_search import search

results = search(
    origin="TPE",           # IATA departure airport code
    destination="NRT",      # IATA arrival airport code
    departure_date="2026-08-08",   # "YYYY-MM-DD"
    return_date=None,       # "YYYY-MM-DD" for round-trip; None for one-way
    adults=1,               # number of adult passengers
    travel_class="economy", # "economy" | "premium-economy" | "business" | "first"
    max_results=5,          # maximum number of results to return
)

Returns: list[dict], each dict has the shape:

{
    "airlines": ["Starlux Airlines"],        # list of airline name strings
    "price": "TWD 8900",                     # price string, or "" if unavailable
    "stops": 0,                              # number of layovers
    "segments": [
        {
            "from": "RMQ",
            "to": "KMJ",
            "departure": "2026-08-08 15:00",
            "arrival": "2026-08-08 18:15",
            "duration_min": 95,
            "plane": "Airbus A321neo",
        }
    ],
    "source": "gf_search",
}

Returns [] if no results are found after retries.

---

build_tfs()

Builds the raw tfs URL parameter (URL-safe base64-encoded protobuf) for the Google Flights search endpoint. Useful if you want to construct URLs manually or inspect the encoding.

from gf_search import build_tfs

tfs = build_tfs(
    origin="RMQ",
    destination="KMJ",
    departure_date="2026-08-08",
    return_date="2026-08-15",   # optional
    seat=1,                     # 1=economy 2=premium-economy 3=business 4=first
    adults=1,
)

url = f"https://www.google.com/travel/flights/search?tfs={tfs}&tfu=EgIIACIA&hl=zh-TW"
print(url)

---

CITY_ENTITIES

A dict mapping IATA codes to Google's city/metro entity IDs. Regular airports use entity_type=1 (handled automatically). Airports that Google indexes at the city level need entity_type=2 with a special entity ID.

from gf_search import CITY_ENTITIES

print(CITY_ENTITIES)
# {
#     "RMQ": "/m/01r8pt",   # Taichung (city entity)
#     "KHH": "/m/0h7h6",    # Kaohsiung
#     "TSA": "/m/02kg86",   # Taipei Songshan
# }

# Add your own:
CITY_ENTITIES["OKA"] = "/m/0h7r_"  # Okinawa Naha

To find an entity ID: open Google Flights in Chrome DevTools, trigger a search for the target airport, and inspect the tfs parameter in the network request.

---

MCP Server (for Claude and AI assistants)

gf-search ships a built-in MCP server. Once published to PyPI, anyone can add it to Claude Desktop with a single config entry — no pre-installation required.

Claude Desktop config (%APPDATA%\Claude\claude_desktop_config.json on Windows, ~/Library/Application Support/Claude/claude_desktop_config.json on macOS):

{
  "mcpServers": {
    "google-flights": {
      "command": "uvx",
      "args": ["--from", "google-flights-search", "gf-search-mcp"]
    }
  }
}

Restart Claude Desktop. Claude will have access to two tools:

• search_flights — single origin-destination search
• search_multi_city_flights — multi-city / open-jaw / 4-leg itineraries

If you prefer installing manually first:

pip install "google-flights-search[mcp]"

{
  "mcpServers": {
    "google-flights": {
      "command": "gf-search-mcp"
    }
  }
}

---

How It Works

Google Flights renders flight data server-side into a <script class="ds:1"> tag. gf-search:

1. Builds a correctly-encoded protobuf tfs parameter (the three fields above are the key)
2. Fetches the page via primp — a Rust HTTP client that impersonates Chrome's TLS fingerprint, so no bot detection triggers
3. Parses all sections in data[3] (Best flights + Other flights), not just the first section, so low-traffic carriers appear
4. Retries up to 3 times with a 1.5 s delay — Google's SSR is non-deterministic; a cold edge cache may return null on the first hit

One-way queries use field_19 = 2 (one-way) with Info.field_16 = INT64_MAX to force full on-demand calculation. No synthetic return date is needed.

---

Limitations

• Non-official API: Google may change the response format at any time.
• SSR non-determinism: Even with the correct protobuf, data[3] is occasionally null on a cold cache hit. The built-in 3-retry logic handles most cases, but very obscure routes may still return empty on some runs.
• Session-dependent carriers (e.g. Cathay Pacific): Some airlines appear in Google Flights SSR only when a valid Google session cookie is present. Since gf-search uses a stateless Rust HTTP client (primp), these carriers may be absent from results on certain routes — even when they appear in a browser. This is a Google-side edge-caching behaviour, not a protobuf issue. Workaround: supplement with SerpAPI or a browser-based fallback.
• Price currency: Prices are returned in TWD (or the locale Google infers from your IP). The hl=zh-TW parameter is set by default.
• No seat map / availability API: This only fetches the search results page, not booking-level availability.

---

Contributing

PRs are welcome! The most impactful contributions right now:

• More city entity IDs in CITY_ENTITIES (any airport where Google uses a city-level entity rather than an IATA code directly)
• Expanded _SEAT_MAP aliases
• Better price currency handling
• Type stubs / py.typed marker

To add a city entity ID, find it via Chrome DevTools as described above, then add it to gf_search/builder.py.

---

License

MIT — see LICENSE.