Methodology

One registry, every figure

Every published figure — a contribution limit, a rate, a threshold, a date — is one row in a registry inside the site’s source code. The row holds the value, its unit, the first and last day it applies, the primary source, the source’s grade, and the day a person last opened that source and saw the number. Pages render figures from the registry. Nobody types a number into prose.

Primary sources only

Figures come from the agency that sets them: Internal Revenue Service revenue procedures, notices and forms; Social Security Administration fact sheets and program rules; the U.S. Treasury’s Fiscal Data API and TreasuryDirect; Department of Health and Human Services poverty guidelines in the Federal Register; Department of Labor COBRA guidance; HealthCare.gov dates. Where a source document could not be read by our tools directly (some IRS PDFs), the figure is graded P′: confirmed from a document quoting the primary text verbatim, with the primary document cited as the source of record. Figures we could not confirm are marked unverified on the page or are not published.

Dated, with an expiry

Each page shows the date its figures were verified and, where the issuing agency has a schedule, the date of the next change: I bond rates every May 1 and November 1; Social Security limits in mid-October for the following year; HSA and HDHP limits in May; ACA applicable percentages in July or August; IRS inflation adjustments, including the health FSA limit, in October or November; HHS poverty guidelines in January.

What the build refuses to publish

• A figure used after its end date. The site cannot be rebuilt on November 1 with October’s I bond rate.
• A superseded value stated as current. Values that have been replaced sit on a deny-list; if one appears outside a history table, publication stops.
• A projection presented as a fact. Unannounced figures are described as “not yet announced” with the expected date, never as an estimate.
• A page without a canonical address, a title, a description, structured data and a verification date.

Calculators are estimates

Rates, limits, dates and rules are exact. Dollar results from a calculator are estimates: Treasury rounds savings-bond values per $25 unit; a Marketplace benchmark premium depends on your county, age and tobacco use; the Social Security Administration withholds whole monthly payments and reconciles later; your plan may set limits below the IRS maximum. Every result page says which figures are exact and which are estimates.

Time

Federal deadlines are calendar dates. The site computes them in America/New_York as whole days and applies the weekend and federal-holiday shifts the IRS publishes, including the effect of Emancipation Day in the District of Columbia on the April deadline. Countdowns are informational; the absolute date is always shown beside them.

Corrections

When a published figure turns out to be wrong, it is corrected and an entry is added below with the date, what was wrong, and how long it stood.

Corrections log

Date	Page	What changed
2026-09-06	—	Site launched. No corrections yet.

Origins

The six calculators were first published in 2026 as separate single-page sites (I bond rate, HSA proration, estimated-tax safe harbor, FSA deadline, Social Security earnings test, COBRA vs Marketplace). Their calculation engines, with their test suites, were carried into Thresholds unchanged and then extended; the figures they used were re-verified against primary sources on 2026-09-06.