calcfinc

Financial ratios you can defend. Every number calcfinc returns comes with the formula that produced it, the exact figures it used, the filing each figure came from, and a plain-language note whenever something was substituted or is missing. Exact decimal arithmetic, no dependencies, and None with a reason instead of a guess.

Apple's return on equity from its own 10-K, in four lines:

from calcfinc import FinancialEngine, SqliteRepositories
from calcfinc.adapters import sec_companyfacts as sec

raw = sec.fetch_companyfacts(320193, "Your Name you@example.com")      # the SEC wants a real contact
repos = SqliteRepositories(":memory:")
sec.load_companyfacts(repos, sec.read_companyfacts(raw), ticker="AAPL")
roe = FinancialEngine(repos).get_ratio("AAPL", "roe", period="FY2025")

roe.value        Decimal('151.9129833317510476991306470644081')     percent, exact
roe.formula      100 * net_profit / total_equity
roe.inputs       net_profit    112,010,000,000 USD   FY2025   reported 2025-10-31   10-K 0000320193-25-000079
                 total_equity   73,733,000,000 USD   FY2025   reported 2025-10-31   10-K 0000320193-25-000079
roe.limitations  ()

Ask for something Apple does not report and you get the reason, not a number:

interest_coverage.value         None
interest_coverage.limitations   ('interest_coverage: finance_costs not reported [FY2025]',)

The same for an Indian exchange filing (Ind-AS XBRL), here Tata Consultancy Services' consolidated results: April-March year, rupees, consolidated and standalone kept apart, and the Schedule III / ICAI ratio forms as india.*. The two TCS filings used here are public regulatory filings, included unmodified in examples/data/tcs so you can run this yourself (the installed package contains no data); for other companies you download the files from the exchange.

from pathlib import Path

from calcfinc import FinancialEngine, SqliteRepositories
from calcfinc.adapters import ind_as_xbrl

repos = SqliteRepositories(":memory:")
ind_as_xbrl.load_xbrl_files(repos, sorted(Path("examples/data/tcs").glob("*Consolidated.xbrl")), entity="TCS")   # basis from the file name
roe = FinancialEngine(repos).get_ratio("TCS", "india.roe", period="FY2025")

roe.value        Decimal('52.16419904858624191565556683948902')    percent
roe.formula      100 * (net_profit - india.preference_dividend) / ((total_equity + prior(total_equity)) / 2)
roe.inputs       net_profit      487,970,000,000 INR   FY2025   31-MAR-2025_Integrated_Filing-_Financials_Original_Consolidated.xbrl   (Rs 48,797 crore)
                 total_equity    957,710,000,000 INR   FY2025   31-MAR-2025_Integrated_Filing-_Financials_Original_Consolidated.xbrl
                 total_equity    913,190,000,000 INR   FY2024   31-Mar-2024_Financial_Results_Original_Consolidated.xbrl
roe.limitations  ('india.preference_dividend not reported; treated as 0 in india.roe',)

Profit is divided by average equity (March 2024 and March 2025), as the Schedule III form specifies, which is why it differs from the plain year-end roe (50.95%). The one input the filing did not carry is announced rather than silently assumed. The figures are TCS's own, as filed. The tour notebook runs this same example in Colab (section 12), after a walk-through on made-up sample files.

Most ratio libraries return a bare float. Here you also get the audit trail: roe.inputs is the list of facts, each with its period, currency, filing and report date, so anyone can recompute the figure by hand or follow it back to the SEC. roe.to_frame() gives that trail as a pandas DataFrame, with the values still exact Decimals.

• Exact. Every number is a Decimal; floats are refused at every entrance. A result is the same on any machine and Python version.
• Honest. A missing input gives None and the reason, never zero and never an estimate.
• Auditable. The formula, every input fact, its filing and report date, and any restatement warning travel with the result.
• Open. More than a hundred ratios, each one a readable formula string (list). Add your own with register_ratio.
• Any entity. Any currency, any fiscal calendar (March, 52/53-week...), months, quarters and years, consolidated and standalone. Banks and insurers get the ratios that suit them; operating-company ratios that mislead return None with the reason.
• Zero runtime dependencies. Python 3.11 or later; pandas is optional.

Status: 0.1, beta. Tested on real filings of 19 US and 20 Indian companies, and checked live on Tesla, Boeing, HCLTech and Titan (see what has and has not been verified). The API may still change in 0.x; changes are listed in CHANGELOG.md.

Try it

pip install calcfinc

Or open the tour notebook in Colab: it runs on built-in sample data, with an optional live Apple download at the end.

Quick start

A CSV with one row per metric and one column per fiscal year:

metric,FY2025,FY2026
revenue,1000,1200
net_profit,100,150
total_equity,500,600
total_assets,2000,2400

from calcfinc import FinancialEngine

eng = FinancialEngine.from_csv("acme.csv", entity="Acme Inc", currency="USD")

roe = eng.get_ratio("Acme Inc", "roe")
roe.value                                        # -> 25
roe.formula                                      # -> 100 * net_profit / total_equity

# growth in percent, FY2025 to FY2026, and compound annual growth
eng.get_growth("Acme Inc", "revenue").value      # -> 20
eng.get_cagr("Acme Inc", "revenue").value        # -> 20

A figure that cannot be computed says why instead of guessing. This file has no cash flow statement:

fcf = eng.get_ratio("Acme Inc", "free_cash_flow")
fcf.value                                        # -> None
print(fcf.limitations[0])

What you can ask

Where data comes from

CSV (long or wide), dicts, pandas, or your own storage; a SQLite file if you want it to persist. Two adapters read real filings:

• SEC companyfacts (US-GAAP): exact periods, restatements kept as versions, the fourth quarter derived, bank lines for banks.
• Indian exchange XBRL (Ind-AS): April-March year, india.* ratios in the Schedule III and ICAI forms, placeholder zeros not loaded.

Both tie every fact to its filing. See docs/adapters.md. No market or vendor data is bundled in the package, and there is no network access except one explicit SEC download helper. (The repository, but not the package, includes two TCS filings for the demo; see examples/data/tcs.)

What it will not do

• Convert currencies. Amounts in different currencies are listed, never ranked.
• Annualise a quarterly ratio. It says "not annualised" and offers the trailing-twelve-month form.
• Hide a substitution. A fallback definition, a derived quarter or a mixed restatement vintage is always in limitations.
• Guess. Where a source concept is not mapped, the metric is absent, not approximated.

Documentation

• Manual: concepts, loading data, periods, every question you can ask, reading results, custom ratios, running it in production, troubleshooting. Its examples are run by the test suite.
• Tour notebook (also tested)
• Ratio and metric reference (generated from the code)
• Fact format and CSV layouts
• Adapters and real-data results
• Examples: seven runnable scripts with synthetic data

Development

python -m venv .venv
.venv/bin/python -m pip install -e ".[dev]"     # Windows: .venv\Scripts\python
.venv/bin/python -m pytest && .venv/bin/ruff check . && .venv/bin/mypy

See CONTRIBUTING.md. To report a vulnerability, see SECURITY.md.

Licence

MIT. Results are calculations, not investment advice.