Local · No uploads

Loan & mortgage amortization calculator

Mobile·FullDesktop·Full

Calculators

Compute monthly payments and a full amortization schedule, with extra-payment payoff — all in your browser.

Mobile·FullDesktop·Full

Your money data never leaves this device

Every calculation, statement, and ledger stays in your browser. Nothing is uploaded, and exports are encrypted on-device.

Loan details

Fixed-rate amortization

Loan amount
Annual interest rate
%
Term (years)
Extra monthly payment
Monthly payment
$1,896.20
Total interest
$382,633.47
Total paid
$682,633.47
Payoff time
30y 0m

Balance over time

Remaining principal at each year

$0.00$74,161.71$148,323.41$222,485.12$296,646.82Y1Y6Y11Y16Y20Y25Y30

These are simplified estimates for planning only — not financial, tax, or legal advice. Figures may be approximate and change over time.

There is no upload endpoint — your files are processed in this browser tab. Open your network tab and check. See how it stays private.

How to loan amortization calculator

  1. Enter the loan. Type the amount, interest rate, and term of the loan or mortgage.
  2. Set the schedule. Choose the payment frequency and start date if needed.
  3. Calculate. See the payment, total interest, and a full amortization table computed locally.
  4. Review or export. Scan how principal and interest shift over the term and export the figures.

An amortization calculator answers the two questions behind any loan or mortgage: what is the payment, and how much interest will it cost over the life of the loan. Seeing the schedule makes the early-years interest load obvious — and shows exactly why extra principal early on saves so much.

Enter the amount, rate, and term to get the payment, the total interest, and a table you can scroll through payment by payment. Because it runs locally, you can model your real balances without sending them to a server.

These figures are for planning and are not financial advice; confirm terms with your lender. To project savings growth instead, use the Compound interest calculator.

Frequently asked questions

What is an amortization schedule?

A row-by-row breakdown of every payment showing how much goes to interest versus principal and the remaining balance — early payments are mostly interest, later ones mostly principal.

Does it handle extra payments?

Where supported, adding extra principal shows how much interest you save and how many payments you cut from the term.

Is this the same as APR?

Not exactly. This uses the nominal interest rate to compute payments; APR also folds in certain fees, so a lender's APR may differ from the rate entered here.

Are my numbers uploaded?

No. Every calculation runs in your browser tab; the loan figures you enter never leave your device.

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PDF stack

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Tool-by-tool: where work runs

Tool / areaWhere work runsExtra network
Merge, split, organize, protectBrowser + workersApp shell only
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Export (PNG / JPEG / text)Browser (pdf.js canvas)App shell only
Forms, watermark, page #, insertBrowser (pdf-lib)App shell only
OCRBrowser (pdf.js + Tesseract)Same-origin WASM/worker/lang after postinstall (no third-party OCR CDN)
Duplicate scan (Organize)Browser worker (pdf.js)App shell only
Share Desk (P2P)Browser WebRTC + OPFS workerSignaling WebSocket + STUN (optional TURN) — no file bytes to SafePaper
Media StudioBrowser + FFmpeg WASM (lazy) + image workersSame-origin FFmpeg under /vendor/ffmpeg/
Data ZoneWeb Workers + DuckDB-wasm + OPFS queuesDuckDB bundles may fetch from jsDelivr on first SQL use — not your table rows
Security VaultBrowser Web Crypto + jose (no upload)Analytics disabled on these routes
AI Desk (RAG)Embedding + chat workers; IndexedDB indexOne-time model weight downloads (Transformers.js / WebLLM CDN)
Record DeskCapture + OPFS mux; Whisper workerWhisper ONNX/WASM may fetch from jsDelivr on first caption run
Vision StudioImage inference worker (ONNX / Transformers.js)One-time model weight downloads (Hugging Face / jsDelivr); images stay local
Audio LabFFmpeg WASM worker + Web Audio; Whisper for transcriptionOne-time FFmpeg/Whisper asset downloads; audio samples stay local
Health Deskdicom-parser + canvas; pure-JS HL7/FHIR; localStorage lab historyNone — scans, records, and lab data are parsed and stored entirely on-device
Scan DeskCamera + canvas image pipeline; Tesseract OCR; pdf-lib exportSame-origin OCR WASM/worker/lang only; scans stay on-device
Diagram DeskMermaid + Graphviz (WASM); canvas rasterize for exportOne-time Graphviz WASM fetch; diagram source stays local
Handwriting DeskCanvas render; MediaRecorder + FFmpeg WASM for videoSame-origin fonts + one-time FFmpeg assets; text stays local
Photo DeskCanvas pixel ops; heic-to WASM decode; RAW preview parseOne-time HEIC WASM assets; photos are edited & encoded on-device
Resume Desk@react-pdf render; pdf.js text extract; localStorageApp shell only; resume data stays in your browser's local storage
Email Deskpostal-mime / msgreader / TNEF parse; DOMPurify + sandboxed iframe (CSP blocks remote); @react-pdf renderApp shell only; email files are parsed in your browser, remote images & trackers blocked by default
Password Deskkdbxweb + hash-wasm Argon2; zxcvbn strength; otpauth TOTP; crypto.getRandomValuesApp shell only; KeePass .kdbx vaults are decrypted & edited in your browser — master password never leaves the tab
Archive Deskzip.js + fflate in archive workerApp shell only (central directory parsed locally)
Data Roomcrypto-packager worker + offline HTML exportSame-origin /dataroom-template.html at build time
Storage DeskArgon2id + AES-256-GCM crypto worker; OPFS + IndexedDB; on-device labeling/embeddingsNone for Browser backend. BYO-S3 sends only opaque ciphertext straight to your own bucket (SigV4) — never to SafePaper

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Offline & limits

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Design rule

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