Purchase invoices, sales billing, the general ledger, expenses, and email campaigns — in one system. Merlin's AI extracts, codes, and posts documents automatically, and gets more accurate with every invoice it processes. Use our hosted version, or self-host for free — it's open source.
Keys the figures into accounting software. Assigns accounts. Files the document. Repeats — every single invoice, every week.
Invoice in one system, books in another, client emails in a third. Every month someone reconciles the gaps — and all those subscriptions add up.
Off-the-shelf tools guess at account codes from general patterns. They don't know that your Supplier A always goes to account 5100.
PDF, Word, Excel or CSV — Merlin extracts every line item, suggests GL account codes from your history, and auto-posts when it's confident. Learns your coding patterns with every invoice.
Create sales invoices, quotes, and credit notes. Set up recurring billing — weekly to annual — with auto-send. Track payments, outstanding balances, and overdue accounts.
Hierarchical chart of accounts, multi-currency expenses with live rates for 160+ currencies, and expense reports by account or supplier. Proper double-entry from day one.
Send invoice emails with custom templates and merge tags. Run email campaigns to contact lists and segments — all from the same system, no third-party email service needed.
Use our hosted version for a monthly fee, or self-host for free — the full source is on GitHub. Either way, there's no proprietary black box. You can always take your data and run it yourself.
Not generic accounting patterns — your suppliers, your accounts, your preferences. The more you use it, the smarter it gets for you.
Speed of automation on invoices Merlin knows well. A clear review queue for anything unusual. No silent errors buried in your accounts.
Purchase invoice processing, sales invoices, quotes, credit notes, and recurring billing (weekly to annual with auto-send). Full chart of accounts, tax handling, and document sequencing — not a simplified tracker.
No server, no setup. We handle hosting, updates, and backups. Pay a monthly fee and start processing invoices the same day.
Merlin is open source under an MIT-style licence. Host it yourself, keep full control of your data, and pay nothing. Community support via GitHub.
View on GitHub →
Generic accounting software knows the rules.
Merlin knows your business.
If you're currently paying someone to key invoices into your accounting software, Merlin is a direct replacement — with a ledger that's always up to date.
No sales funnel. Just a conversation about your use case.
Tell us a bit about your business and we'll be in touch.