Every invoice gets a SHA-256 integrity seal and a permanent public verify link. Your client can't argue with a receipt they can verify themselves. Contractor billing disputes, freelancer hours proof, tamper-evident timesheets — all closed. One click. No login. No doubt.
Every contractor, freelancer, and agency faces the same three silent failures. GAP Receipts closes all three.
Without a tamper-evident paper trail, you lose by default. GAP Receipts generates a public verify URL with every invoice — the client confirms it or they don't, and either way it's on record. You got the receipts. That's the end of the argument.
Clients who question your hours need more than your word. A verifiable invoice — with a SHA-256 hash stored at generation time — is tamper-evident proof of every line item. Freelancer hours proof. Verifiable invoice. One link. No argument.
The verify page your client opens is SHA-256 sealed at creation. Any change to amounts, dates, or line items breaks the hash — instant detection. It's not a PDF they can edit. It's a permanent record they can check themselves.
Create via REST API or the web app, share a link, get paid. Stripe handles the money; we handle the proof.
POST to /v1/invoices or use the web form. Attach line items, amounts, and your Stripe account. The system generates a SHA-256 hash of the final document and stores it alongside the invoice record.
Every invoice gets a permanent, public URL at /verify/INV-XXXX. Send it to your client by email, text, or embed it in your system. The verify page shows invoice details and a live integrity badge — no login required.
The verify page includes a Stripe Checkout button. Your client clicks "Pay Now," goes through Stripe's hosted checkout flow, and payment routes directly to your connected Stripe account. You see the money. The verify page updates to "Paid." Done.
Click through each step below — or see a live signed invoice in production → or try the product directly →
# Create a tamper-evident invoice
POST https://gap-receipts-api.pages.dev/v1/invoices
Authorization: Bearer gr_live_••••••••••••••••
Content-Type: application/json
{
"client_name": "Lakeside Marine LLC",
"client_email": "billing@lakesidemarine.com",
"currency": "usd",
"line_items": [
{ "description": "Engine service & winterization", "qty": 1, "rate": 850.00 },
{ "description": "Marine antifreeze (6 gal)", "qty": 6, "rate": 18.50 }
]
}
── Response 201 ─────────────────────────────────────
{
"ok": true,
"invoice_number": "INV-2026-0041",
"total": 961.00,
"verify_url": "https://gap-receipts-api.pages.dev/verify/INV-2026-0041",
"hash": "sha256:a4f9e2c1..." ← tamper-evident seal
}
# What your client sees when they open the verify link
From: Lakeside Marine LLC
✓ Tamper-evident
The SHA-256 hash embedded in this page matches the one stored at invoice creation. Any edit to amounts or line items would break the match — instantly detectable.
✓ No login required
Clients open the link and see everything. No account, no app install, no friction.
✓ White-label ready
Agency tier includes custom logo, colors, and domain on every verify page.
# Live demo — paste any job description and hit Parse
# Create a scoped REST API key for your integration
POST /api/keys
{
"label": "Shopify post-checkout automation",
"scopes": "invoices:read,invoices:write",
"rate_limit": 1000
}
── Response 201 ─────────────────────────────────────
{
"ok": true,
"api_key": "gr_live_a9f2c4e8d1b3...", ← shown once, store it now
"scopes": "invoices:read,invoices:write",
"rate_limit": 1000,
"warning": "Store this key securely — it will not be shown again."
}
# Keys are SHA-256 hashed before storage. Plaintext never persisted.
# List keys: GET /api/keys · Revoke: DELETE /api/keys/:id
↑ All endpoints live now at gap-receipts-api.pages.dev · Runs on Cloudflare Workers + D1 · <50ms globally
Most invoicing tools do one or two of these. GAP Receipts ships all six in every tier.
Every invoice gets a SHA-256 hash stored at creation time. If any field changes — amount, date, line item — the hash breaks. Clients and courts can verify in one step.
UniqueEvery invoice gets a permanent public URL. Share it by email, text, or embed it in your system. No login. No app. Clients open the link, see the details, pay. Done.
UniqueAgency tier includes custom logo, brand colors, and custom domain on every verify page. Your clients see your brand — not ours. Fully white-labeled, fully yours.
Paste a job description in plain English. The AI returns structured line items with descriptions, quantities, and rates — ready to push to an invoice. Claude + Groq fallback.
UniqueCreate API keys with specific scopes (invoices:read, parse:read) per integration. SHA-256 hashed, shown once, instantly revocable. Build any automation on top.
Connect your Stripe account once. Every invoice gets a live Checkout button. Payment routes directly to you — not through GAP. No float, no middleman hold, no delay.
QuickBooks, Wave, and FreshBooks are great general-purpose tools. None of them were built around proof of authenticity. GAP Receipts was.
| Feature | GAP Receipts | QuickBooks | Wave | FreshBooks |
|---|---|---|---|---|
| Tamper-evident SHA-256 signing | ✓ Every invoice | ✗ | ✗ | ✗ |
| Public verify link (no login) | ✓ Permanent URL | ✗ | ✗ | ✗ |
| REST API for invoice creation | ✓ Full + scoped keys | ⚬ Accounting API only | ✗ No API | ⚬ Limited |
| AI line-item parser | ✓ Claude + Groq | ✗ | ✗ | ✗ |
| White-label branding | ✓ Agency tier | ✗ | ✗ | ⚬ Limited logo only |
| Stripe Connect direct payments | ✓ Direct · 0% GAP markup | ⚬ QuickBooks Pay (fees) | ⚬ WavePay (fees) | ⚬ FreshBooks Pay (fees) |
| Multi-seat / Teams | ✓ Pro + Agency tiers | ✓ | ⚬ Limited | ✓ |
| Starting price | $29/mo | ~$18–35/mo | Free (payment fees) | ~$19/mo |
✓ = included ⚬ = partial/limited ✗ = not available. Competitor pricing approximate and subject to change.
No contracts, no setup fees, no per-invoice charges. GAP Receipts takes 0% of your transactions — your subscription is the only cost you pay us. Stripe charges standard processing rates when clients pay.
Billed monthly. Subscription auto-renews until cancelled — no cancellation fee, cancel anytime from your account. No setup fees, no per-invoice charges. Terms of Service · Privacy Policy
Create an account at gap-receipts-api.pages.dev, connect Stripe, and send your first sealed invoice. Available immediately.
Bronze / Silver / Gold clients: request GAP Receipts integration in your onboarding checklist. Provisioned within 24 hours of project kickoff.
REST API live at gap-receipts-api.pages.dev/v1/. OpenAPI spec available. Custom integration: contact Sales@.
GAP Receipts generates a sealed invoice with a SHA-256 hash stored at creation time. Send your client the verify link — they open it, see every line item, and confirm the hash matches. Any alteration to hours or amounts breaks the hash instantly. You don't need to argue; the receipt proves itself.
A tamper-evident invoice is one where any change to amounts, dates, or line items is detectable. GAP Receipts stores a SHA-256 hash of the invoice content at generation time. If anything changes after generation, the hash breaks — and anyone with the verify link can see that instantly, without logging in.
The root cause of billing disputes is the absence of a verifiable record. A PDF can be edited by either party in 60 seconds — there is no way to prove who changed what. GAP Receipts creates a public verify URL that belongs to neither party. Your client verifies against it or they can't — and that single change ends most disputes before they start.
Yes — that is the primary use case. The Solo tier ($29/mo) is built for freelancers and solo contractors. You create an invoice, attach your hours and line items, and the system generates a verify link you send with every invoice. Clients see your sealed record. No more "I didn't agree to that" — the hash was sealed at the time you submitted it.
Invoice integrity proof means independently verifiable evidence that an invoice has not been altered since it was created. GAP Receipts provides this via SHA-256 hash-based tamper detection: the hash is stored publicly, and any client can recompute it against the current invoice content. If they match, the invoice is unaltered. If they don't, something changed.
There is no free tier — GAP Receipts starts at $29/mo for the Solo plan. There are no contracts, no setup fees, and no cancellation fees. Cancel anytime from your account settings. The verify product at tbb-work-report.pages.dev is a live production invoice you can inspect for free before subscribing.
GAP Receipts takes 0% of every transaction — your subscription is the only cost you pay to GAP. When your client pays through the verify page, Stripe's standard processing rates apply: 2.9% + $0.30 per card transaction, or 0.8% capped at $5 for ACH bank transfers. These are Stripe's fees, not GAP's. Funds go directly to your connected Stripe account — GAP never holds or passes through your payments. Platforms like QuickBooks Pay and WavePay use their own payment systems and set their own rates; GAP Receipts connects directly to your existing Stripe account at Stripe's published rates with 0% GAP markup.
Connect Stripe, send your first tamper-evident, SHA-256 sealed invoice in under 10 minutes. You got the receipts. Your clients can verify them. Done.