Documentation
Everything you need to get the most out of Voince.
Overview
Voince extracts structured data from PDF invoices using a language model that runs locally on our own server. Your invoice is never sent to OpenAI, Google, Anthropic, or any other external AI provider.
The pipeline is simple:
- You upload a PDF invoice.
- We extract the text layer (no OCR — see Scanned PDFs).
- The AI model extracts structured fields: supplier, invoice number, dates, amounts, line items.
- Deterministic Python validation checks arithmetic, required fields, and business rules.
- You review, edit if needed, and approve or reject.
- Export to CSV or Excel with one click.
How it works
Each upload goes through four stages, all in a few seconds:
| Stage | What happens |
|---|---|
| PDF extraction | We read the text layer of your PDF using pypdf. Typically under 100 ms. |
| AI extraction | Llama 3.2 (1B) reads the text and returns structured JSON. Typically 1–5 seconds. |
| Validation | We check subtotal + tax = total, sum of line items, required fields. Under 10 ms. |
| Storage | The invoice, line items, and validation result are saved to your account. |
Uploading an invoice
- Open Upload from the navigation bar.
- Drag a PDF file onto the drop zone, or click to browse.
- Click Process Invoice.
- Wait a few seconds — you'll be redirected to the result page.
Limits
- File type: PDF only (text-based, not scanned)
- Maximum size: 10 MB
- Monthly limit: 10 invoices (Free) or 100 invoices (Pro)
Reviewing results
After extraction you'll see two columns: the extracted fields on the left, and validation results + actions on the right.
- Invoice — supplier, invoice number, dates
- Financial — currency, subtotal, tax, total
- Line items — description, quantity, unit price, total
- Validation — green if all checks pass, yellow for warnings, red for errors
Click Edit to correct any field or line item. Saving re-runs validation automatically.
Business rules
After each extraction and edit, Voince runs these checks:
| Check | Type |
|---|---|
| Supplier name present | Error |
| Invoice number present | Error |
| Total present | Error |
| Subtotal + tax = total | Error |
| Invoice date present | Warning |
| Due date present | Warning |
| Currency present | Warning |
| Line items present | Warning |
| Sum of line items = subtotal | Warning |
Errors must be fixed before you should rely on the data. Warnings don't block approval but suggest you double-check.
Line items
Line items are extracted individually. If the AI misses a row or misreads a quantity, open Edit and:
- Click + Add line item to add a missing row.
- Click the × button to remove an incorrect row.
- Correct Description, Qty, Unit price, or Total inline.
- Click Save changes — validation re-runs automatically.
Approve & Reject
On the result page you have two actions:
- Approve — marks the invoice as reviewed and final.
- Reject — marks it as rejected (e.g. duplicate or not relevant).
- Edit — change fields before approving.
Approval status is shown in the Invoices list with a coloured badge.
CSV / Excel export
- Single invoice: on the result page, click CSV or Excel.
- All invoices: on the Invoices page, click
Download CSV, or use
/invoices/export.xlsxfor the full Excel.
Exports include all header fields and line items. Column layout is stable — safe to import into accounting software.
Deleting invoices
On the Invoices page, click the trash icon next to any invoice. Confirmation is required. Deletion permanently removes:
- The database record (invoice, line items, validation)
- The uploaded PDF file from our server
This action cannot be undone.
Free vs Pro
| Feature | Free | Pro |
|---|---|---|
| Monthly invoices | 10 | 100 |
| AI extraction | ✓ | ✓ |
| Validation & editing | ✓ | ✓ |
| CSV / Excel export | ✓ | ✓ |
| Priority processing | — | ✓ |
| Price | $0 / month | $10 / month |
Upgrade on the Pricing page. Payment is in crypto via Trybit.
Adding funds
Voince uses an internal balance:
- Open Add funds.
- Enter an amount (min $10, max $500).
- You're redirected to a Trybit checkout.
- Pay in crypto from any wallet.
- Your balance updates when Trybit confirms the payment — usually within a minute.
Subscription & renewal
The Pro subscription is charged automatically from your balance each month on the same date.
- If your balance is enough — renewed automatically.
- If not — you're marked past due and keep access until the current period ends.
- If the period ends without payment — you're downgraded to Free.
- You can cancel from Account — you keep access until the end of the paid period.
Google / GitHub sign-in
You can sign in with email/password, Google, or GitHub. If you registered with a password and later sign in with Google using the same verified email, accounts are linked automatically.
Email & password
From Settings you can:
- Change your email
- Change or set a password
- Delete your account permanently
Privacy & security
- All data is isolated per user — no user can see another user's invoices.
- All traffic uses HTTPS (TLS 1.2+).
- Passwords are hashed with bcrypt — we cannot recover them.
- AI runs locally, on our own server. No external AI provider.
- Daily backups of the database are performed.
See the full Privacy Policy and Terms of Service.
Scanned PDFs
Voince works with PDFs that have a selectable text layer — the kind produced by accounting software, Word, LaTeX, or any modern PDF generator.
Scanned documents — pictures of paper invoices saved as PDF — have no text layer. Voince cannot process them (OCR is not supported yet). You will see a clear error message and no invoice will be created.
Monthly limit reached
The monthly counter resets on the 1st day of each calendar month (UTC). If you reach your limit before that:
- Wait for the reset, or
- Upgrade to Pro for 100 invoices per month.
Extraction errors
Common issues and what to do:
| Symptom | What to do |
|---|---|
| "This PDF appears to be a scanned document" | Use a PDF with a text layer. See Scanned PDFs. |
| "AI could not understand the document" | Try again, or edit fields manually. Rare for typical invoices. |
| Missing line items | Open Edit and add missing rows manually. |
| Wrong amount or date | Open Edit and correct. AI can misread unusual layouts. |
| "Payment service is temporarily unavailable" | Trybit API is unreachable. Try again in a few minutes. |
Contact us
Still stuck? We're happy to help.
- Support: [email protected]
- Privacy & data requests: [email protected]