Not legal advice — Denial Decoder helps you understand insurance denials; it doesn't replace a licensed attorney, doctor, or patient advocate.

Denial Decoder
For patients, by patients

Your insurance denial, decoded.

Paste your denial letter or upload a photo. In about thirty seconds you'll get a plain-English explanation, your appeal deadline, the exact escalation steps, and a list of documents to gather.

  • No account required
  • Nothing stored on our servers
  • PPO • HMO • Medicare • Marketplace
≈80%of appeals that get filed are overturned
<1%of denied claims are ever appealed
30 secto understand your letter

From confusing letter to clear next step in 30 seconds

The letter you got
Denied

NORTHSHORE HEALTH PLAN — ADVERSE DETERMINATION

Claim #2026074155001 · CPT 70551

DETERMINATION: DENIED (MN-02).

Services not deemed medically necessary per plan medical policy; conservative treatment not documented prior to advanced imaging.

You may request internal appeal within 180 days.

What Denial Decoder gives you
Medical necessity

Here's what it actually means

They denied your MRI because they want proof you tried 6 weeks of conservative treatment first.

Appeal by Sep 10, 2026

Next step: Ask your doctor for a Letter of Medical Necessity, then file your internal appeal.

Plain-English readDeadlineEscalation stepsDocuments to gather

Real example, simplified. Your letter is never stored.

How it works

Denial letters are written by underwriters, for underwriters. We translate them into something you can actually act on.

Drop in your letter

Paste the text or upload a photo / PDF. We support PPO, HMO, Medicare, Medicaid, and ACA plans.

Get the real read

We extract the denial reason, your deadline, and the relevant plan rules — in plain English.

Take the next step

Follow the escalation ladder, gather the right documents, and (optionally) generate a formatted appeal letter.

For patients, by patients

Built from a letter we almost gave up on

Denial Decoder started with a letter my father got — a denial none of us could understand, with a deadline we almost missed. We learned the hard way that most denials can be appealed, and that most people never do. So we built the tool we wish we'd had: paste your letter, get it in plain English, and know exactly how to fight back. For patients, by patients.

Built around your privacy

We don't keep your letter, your decoded result, or any appeal content you generate. The analysis happens on demand and is discarded as soon as the response is returned. We don't log letter content.

  • No accounts, no profiles, no tracking pixels in your letter.
  • AI explanations are sourced from a curated knowledge base, not the open web.
What you get
  • Plain-English read of the denial reason
  • Your appeal deadline & how to count the days
  • Step-by-step escalation ladder
  • Checklist of documents to gather
  • Optional: formatted appeal letter PDF
Start decoding