Math you can audit.
Mesfonic is built by a CPA who kept watching the same failure mode: an employer receives a compliance notice, panics, and either ignores the math or pays someone else to do arithmetic they could check themselves.
The notices are formula-driven. Letter 226-J is a month-by-month listing compared against published codes and three published safe-harbor formulas. That work is deterministic — it doesn't need judgment, it needs care. So we built the care into software: every figure cites its source, every output shows its work, and the same inputs always produce the same outputs.
What we believe
- Primary sources or nothing. If a figure can't be traced to the IRS, the statute, or HHS, it doesn't ship as fact.
- No AI in the loop. These tools are explicit code — lookups and arithmetic. Nothing is generated or guessed.
- Honesty over conversion. The free check tells you when the pack doesn't fit. We'd rather lose a sale than sell the wrong tool.
- Your data stays yours. Builder inputs never leave your browser. Our analytics can't identify you because they never try.
What we're not
We're not a law firm, not a tax practice, and not your advisor. The tools map facts to published rules; they don't tell you what to argue or predict outcomes. For advice about your situation, talk to a qualified professional — ideally before your response date.
Questions? [email protected] — we reply within one business day.