Supported document type
Detect tampered and deepfake Amortization Schedule
An amortization schedule is a loan's repayment plan written out row by row, and it is pure arithmetic: given a principal, a rate, and a term, every figure is determined. That makes it one of the few financial documents where a checker can prove an edit rather than suspect one. A schedule that does not reproduce from its own header, or that never reaches zero, was not produced by a lender's system.
API slug: amortization_schedule
What a genuine amortization schedule contains
The schedule starts with the loan amount, interest rate, term, instalment, and start date. Its table lists each period with a payment number, a date, the payment, the interest portion, the principal portion, and the remaining balance. Some versions add cumulative interest and principal columns and a totals row for the life of the loan.
Each row follows from the previous one. Interest is the opening balance multiplied by the periodic rate, principal is the payment less interest, and the closing balance is the opening balance less principal. On a level-payment loan the instalment is constant, interest falls, principal rises, and the last row brings the balance to zero within rounding. The row count must match the term.
How amortization schedule forgeries are made
Term and rate substitution
Rate or term is changed in the header to make the loan look cheaper or shorter, without recomputing the table. The rows no longer follow from the header, which is verifiable in a few lines of arithmetic.
Spreadsheet regeneration
The whole table is recalculated in a spreadsheet with altered terms and exported to PDF. Internal arithmetic passes, so the evidence is in the file: a uniform text layer and production traits no lender system leaves.
Final row forcing
The last balance is set to zero by hand after earlier rows were altered. The final instalment then differs by more than rounding, or the sum of principal does not equal the loan amount.
Totals edits
Total interest paid is lowered to disguise the cost of credit. The column no longer sums to the printed total, a check that takes seconds once the rows are read.
What TamperCheck checks on an amortization schedule
TamperCheck runs 200+ forensic checks across three layers and returns a risk score from 0 to 100 with plain-English findings tied to specific regions of the document. These three carry the most weight on this document class.
Arithmetic reconciliation
Stated totals are recomputed from their components, and running or cumulative figures are checked for continuity across periods. A single edited value breaks the chain even when the page still looks right.
Table structure integrity
Inserted and deleted rows leave structural artifacts behind: inconsistent spacing, misaligned columns, and formatting the visible table no longer accounts for.
Date and validity consistency
Issue, expiry, and period dates are checked against one another and against the file's own creation metadata, which catches backdating and validity extension.
And many more checks
The three above are the layers that carry the most weight on an amortization schedule. Every upload runs the full suite of 200+ checks regardless of document class, spanning file structure and metadata, pixel-level forensics, font and text rendering, optical and print characteristics, provenance signals, AI-generation signatures, and many more checks.
Who verifies an amortization schedule, and why
Underwriters, auditors, and lenders reconciling loan terms. In each case the document is being used to unlock money, access, or a legal status, which is exactly what makes it worth forging.
How to verify an amortization schedule in 4 steps
Check the fields against each other
Read interest and principal split, remaining balance, and instalment amount together rather than one at a time. Forgers typically change one value and leave the rest of the document describing the original.
Inspect the file metadata
Open the document properties and look at the producer, creation date, and modification date. A document produced by a consumer PDF editor, or created long after the date printed on its face, is worth a closer look.
Ask for a second document
Request a corroborating document from the same issuer or an adjacent period. Forgery effort concentrates on one file, so inconsistencies surface as soon as there are two to compare.
Run a forensic check
Manual review catches obvious edits but not field-level pixel manipulation or synthetic generation. TamperCheck runs 200+ forensic checks on an amortization schedule and returns a risk score from 0 to 100 in about a minute, at $0.50 per document.
Frequently asked questions
How do I check that an amortization schedule adds up?
Recompute a few rows: interest as opening balance times periodic rate, principal as payment less interest, then the new balance. Confirm the instalment is constant, the balance reaches zero at the last row, and the printed totals equal the column sums.
Can a loan repayment schedule be faked?
Yes, and a consistent one is easy to generate with a calculator. That is why arithmetic alone is not proof. A forged schedule that reconciles still tends to show the wrong producer traits in the file, and it should also be compared with the lender's sanction letter and actual bank debits.
Why does interest fall over the life of the loan?
Because interest is charged on the outstanding balance, and each instalment reduces that balance. Early payments are mostly interest and later ones mostly principal. A schedule where the interest column is flat on a reducing balance is not a standard amortization.
Is an amortization schedule the same as a payment schedule?
No. An amortization schedule splits each loan payment into interest and principal and tracks the balance. A payment schedule simply lists what is due and when for a fee, tuition, or purchase plan, with no interest mechanics behind it.
TamperCheck analyses amortization schedule uploads with a hybrid forensic and AI pipeline tuned for this document class. Upload endpoints accept PDF and common image formats; class is inferred automatically. See the API documentation for authentication, async jobs, and webhooks.