Yes: on MedBillCheckup, your browser reads the bill on your own device, and the bill file stays there. To run the checks, the charge lines, dates and totals are sent to our server, and they are not kept.
Not every bill checker works that way. Some take the file itself.
What are the two ways a bill checker can work?
A checker has to get the words and numbers off your bill before it can check anything. It does that in one of two places.
On the company's server. You upload the file. The company's computer reads it and sends back a result. While it reads, your file is on a computer you do not control. After that, the company's own rules decide whether the file is deleted or kept.
In your browser. The page reads the file on your phone or computer. A web page can open a file you choose and read what is in it without sending the file anywhere. Sending it would be a separate step that the page has to take.
Reading in the browser tells you where the file is read. It does not tell you everything the page sends. A tool that reads in the browser may send nothing, or it may send the figures its checks need. So ask about both.
What does each way mean for your file?
A bill carries more than charges. It usually has your name, your address, an account or member number and the name of the provider. A file that is uploaded takes all of that with it. A file that is read in the browser stays on your device, and the company gets only what the tool then sends for its checks. So ask what that is.
What happens after that depends on the company. With an upload, you rely on what it does with the file. With a tool that reads in the browser, you rely on what it sends from the bill, and whether it keeps that.
What does MedBillCheckup send, and what stays on your device?
Your browser reads the bill. It takes the text from a PDF, or turns a photo into text with a model that runs on your device. The charges are sent only when you ask for the checks, and nothing is kept.
Stays on your device
- The bill file and its pictures
- Your name and address
- Account and member numbers
- Date of birth
Sent to be checked, then not kept
- Charges, their descriptions and the organization that billed them
- Billing codes
- Amounts and dates
- Your answers to the money questions
- The country you chose
Names and numbers stay wherever your browser recognizes them. The Security page lists everything a check sends.
The checks are fixed, written rules, not an AI model.
Have your bill in front of you? Check it now, free. Your bill file stays on your device.
Check my bill, freeHow can you tell which kind a checker is?
Ask these questions before you give any tool your bill.
- Does it ask you to upload? A button or a heading that says "Upload" often means the file goes to a server, but some tools use the word for any file they open. A file picker alone does not tell you, because both kinds use one. The next questions settle it.
- Does its privacy policy say files are stored? Look for the words "upload", "store", "keep" and "delete". A policy that says files are stored should also say how you can have them deleted.
- How long are they kept? A stated period, such as a number of days, is an answer. A policy that does not say is not an answer. If you cannot tell, ask the company in writing before you send the bill.
- What does your browser show? If you are comfortable with browser tools, open the Network panel before you choose the file. In Chrome it is in the developer tools, and it lists what the page sends while it is open. A tool that uploads your file shows a request that sends it.
What should you do with a checker's result?
Treat what any checker finds as a list of things worth asking about, not as a ruling. Only the provider or your insurer can confirm what you owe. CMS suggests starting with the provider's billing department and, if you used insurance, your health insurer.
- Get an itemized bill if you only have a total. Our free itemized bill letter writes the request.
- Ask about one line at a time. For example: "Can you explain this line? I see the same code twice on the same date." Write down who you spoke to, the date and what they said.
- Compare the bill with your EOB before you pay. Our guide on bills and EOBs shows which numbers should match.
Our medical bill checklist goes through the checks in order, and how to question a medical bill covers what to do when the billing office answers.
Check your bill on your device
Open your bill in MedBillCheckup: take a photo or choose the PDF. Your browser reads it, and the file stays on your device. The charges are sent only when you ask for the checks, and nothing is kept. The free check shows how many things are worth asking about. When a money check finds something, it also shows the largest amount worth asking about. The full list is paid: every line, why, and the question to ask for each. It never says a charge is wrong; only your provider or insurer can confirm that.
Want a second pair of eyes on your bill?
Check it free. Your bill file stays on your device.
Questions about this guide
Does MedBillCheckup upload my bill?
Not the file. Your own browser reads the bill, and the bill file stays on your device. For the checks, the charge lines, dates and totals are sent to our server, which runs the checks in memory and keeps nothing.
If a checker reads my bill in the browser, does it send nothing?
Not always. Reading in the browser means the file is read on your device. The tool may still send figures from the bill to a server for its checks. Ask what it sends, and read its privacy policy.
Are the checks done by AI?
No. The checks are fixed, written rules, and each thing worth asking about comes with its reason. On your device, a text-recognition model turns a photo into text, and with Pro a second model matches a typed question to answers we wrote. Neither judges the bill.
Can a checker tell me that a charge is wrong?
No. A checker can show what may be worth asking about. Only your provider or insurer can confirm a charge, so ask the billing office about the lines you find.
Sources
- MDN Web Docs: Using files from web applications
- Chrome for Developers: Inspect network activity
- Centers for Medicare & Medicaid Services: Check your medical bill for errors
Related guides
- Medical bill checklist: what to check before you pay
Ten things to check on any US medical bill, from dates and totals to your EOB.
- How to read a medical bill
A line-by-line walkthrough: what each amount means, and which numbers should agree.
- What is an itemized medical bill, and how to get one
Why it’s the first thing to ask for, what it should contain, and a free letter you can send.
- Medical bill mistakes and errors: common kinds and how to check your bill
Eight common kinds of medical bill mistakes and errors, how to check your own bill for them, and the question to ask about each.
Free tools
- Itemized bill request letter
Ask the provider for every charge, line by line.
- Refund request letter
Ask for a credit balance back when you paid more than your share.
- Financial assistance request letter
Ask a hospital for its financial assistance policy and application form.
- Charity care check
See whether you may qualify for a hospital’s financial assistance.
- Letter to a collection agency
Dispute a medical debt, or ask the agency for verification.
- Medical bill dispute letter
Ask the billing office about the charges you type.
- Insurance claim file request letter
Ask a health plan for the documents behind a decision on a claim.
- Medical bill code lookup
Medicare’s name for a drug, supply or equipment code on your bill.
- Health money dates 2027
Open enrollment, FSA, Medicare and tax dates for 2027, each with its source.
- Medical bill glossary
The words and abbreviations on bills and EOBs, explained.