Nº 01In the browser
Send a letter online
No accountWrite your text or paste it in. Add the recipient and sender and pay. You see the price before you pay. Runs in the browser, nothing to install.
Write a letter in your browserReal letters · no printer, no stamps
The easiest way to send a real letter.
Write your letter in the browser, start from a ready-made template or let your AI assistant write it. FrankKi prints it, puts it in an envelope and hands it to the post, in Germany and worldwide.
Without an account, in the browser or with a template, you see the price of your letter before you pay. The volume price of €1.59 to €1.99 per standard letter applies only to businesses with a business account. Prefer your iPhone? In the app a standard letter starts at €3.49.
No account needed in the browser/Worldwide: Deutsche Post and partners/No subscription, you pay per letter
WorldwideGermany, France and 200+ destinations
WRITE
PRINT
SEND
DELIVERED
Sent by your AI agent
Delivered by
Germany
Other destinations
Switzerland
France
Netherlands
United Kingdom
Austria
Belgium and Luxembourg
Spain
India
Delivered by Deutsche Post and postal partners worldwide. Posted from the browser, the app or your AI assistant.
Claude·
ChatGPT·
Cursor·your own agent
Claude·ChatGPT·Cursor·your own agentNº 01Five ways
Five ways to send a letter.
You type the text in the browser, fill in a template, ask the app or let your AI assistant write it. The ending is always the same: FrankKi prints, franks and hands the letter to the postal service, in Germany and worldwide.
Nº 02From a template
The templates
No accountCancellations, appeals, withdrawals, objections to a tax assessment, payment reminders. Pick the template that fits, fill in your details and the recipient, pay for the letter and it goes out. No sign-up, no install.
frankki.app/vorlagenNº 03For business
With your AI assistant
Your AI assistant writes · liveConnect Claude, ChatGPT or another AI assistant to FrankKi once. After that one sentence in the chat is enough: write client X a payment reminder. FrankKi prints it on your letterhead and sends it as soon as you approve.
How it works in the officeNº 04On your phone
The iOS app
FrankKi helps you writeTell the app what it is about. FrankKi drafts the letter for you. You read it over, adjust and tap send. Address, form and postage are handled in the background.
On the App Store · Android soonNº 05In ChatGPT
The ChatGPT app
Coming soonDescribe the letter in the conversation, FrankKi drafts it, you pay on our own checkout page and the letter goes out. No install, no account. The date lands here once the app is approved.
In progressNº 02How it works
And then? Print. Frank. Post.
What happens after you hit send.
01
Your text arrives
From the app, from the browser or from your agent. To FrankKi it is the same letter.
02
FrankKi prints and encloses
On real paper, folded and enclosed to DIN 5008. Companies print on their own letterhead.
03
The postal service takes over
Deutsche Post within Germany, local postal tariffs across DACH and several European countries, DHL to the rest of the world. Registered mail is available where the destination supports it.
04
Delivered, worldwide
In Germany usually within 1 to 3 working days, from a business account within 2 to 4, in the rest of the world typically 4 to 18 business days. With tracking your agent can read too.
Nº 03For business · live
Your AI assistant writes the letters. You approve them.
It also works without an AI assistant. On a business account you write an invoice, payment reminder or dunning letter yourself in the browser, on your letterhead. Enter line items and recipient, check preview and price, approve.
For offices, law and tax firms and trades that send invoices, payment reminders or letters to tenants. Connect Claude or another AI assistant to FrankKi once. After that one sentence in the chat is enough, and the letter arrives in print.
The connection between Claude and FrankKi is called MCP. You do not have to write any code.
How it works in the office
Create a business account. Signing up costs nothing. Before your first letter you sign the data processing agreement (AVV), enter your sender details and top up your balance.
Connect Claude. You add FrankKi in Claude as a connector and confirm in the browser with your FrankKi account.
Tell Claude what to send. For example: send Weber GmbH a payment reminder for invoice 2026-118.
Check the preview and price, then approve, in the dashboard or, if you allowed it when connecting, right in the chat. FrankKi prints the letter, puts it in an envelope and hands it to the post.
Nothing goes out without your approval. The exception is autopilot, which only you can switch on, with fixed limits per day and month.
Nº 04What people and agents use FrankKi for
The paperwork that can't be handled by email.
Exactly where a real letter counts, with a date, proof and a signature. Typed by you or posted by your AI agent.
Cancellations
Gym, mobile, energy, insurance. Out on time, with proof.
Letters to authorities
Tax office, agency, application. Correct form and on time, without a trip to the post office.
Invoices & payment reminders
Your AI assistant writes the reminder to client X, FrankKi prints and sends it. With a date and proof.
Objections & deadlines
Fines, notices, appeals. You see when the letter is expected to arrive. You work out the deadline yourself.
Tenancy matters
Defect notices, cancellations, objections to the service-charge statement.
Mail merges
Many recipients, one template. Your AI assistant posts them all in one go.
Nº 05Pricing
Letters from €1.59.
With a business account on the web, a German standard letter starts at €1.59, including print, envelope and postage. Your monthly volume sets one price for every letter that month, including the first.
- German standard letter: €1.59 from 1,000 · €1.69 from 500 · €1.79 from 100 · €1.89 from 20 · €1.99 below 20 letters a month
- Registered mail from €5.59 for Einwurf or €5.99 for Übergabe
- You see the exact price before you or your agent approves the send
The card shows the price of a single letter in the iPhone app. In the browser and with a template you see the price of your letter before you pay. With a business account on the web the volume prices on this page apply. There is no subscription or minimum term. Business pricing
German standard letterSingle letter in the app · no business account
Print, envelope and postageincluded
Totalfrom €3.49
Registered mail, total price per letter
Einwurf-Einschreiben€7.59Übergabe-Einschreiben€8.19
FAQ
Good to know.
How fast does my letter arrive?
Within Germany, Deutsche Post delivers around 95% of letters at E+3 and 99% at E+4, so three to four working days after posting. After printing, FrankKi shows you an expected delivery window that counts weekends and the public holidays where the recipient lives. You work out your deadline yourself and leave a buffer when it is tight. Internationally, transit time depends on the destination country.
Can I send registered mail?
Yes. You choose between Einwurf-Einschreiben with an Einlieferungsbeleg (proof of posting) and Übergabe-Einschreiben against a signature, depending on how much proof you need. For most deadline-bound letters, Einwurf is enough.
How do I send letters with my AI assistant?
Connect your AI assistant to FrankKi once. In Claude you add FrankKi as a connector and sign in with your FrankKi account. It also works with ChatGPT, Cursor or VS Code. The connection is called MCP, and you do not have to write any code. After that your assistant drafts letters, tells you the price and sends them worldwide. The approval stays with you.
What does FrankKi cost?
It depends on how you send. In the iPhone app a standard letter starts at €3.49. In the browser and with a template you see the price of your letter before you pay. On a business account you pay €1.59 to €1.99 per standard letter, depending on your monthly volume. Print, envelope and postage are always included. There is no subscription and no minimum term, you only pay for the letters you actually send.
Does it work internationally?
Yes. FrankKi sends worldwide. Across DACH (Germany, Austria, Switzerland) and several European countries your letter runs at local postal tariffs through the postal service in the destination country, Deutsche Post within Germany. The rest of the world goes by DHL, typically in 4 to 18 business days. You write as usual, we take care of the rest.
Guides
From the blog
Guides, templates and sample letters.
Send physical letters with Hermes Agent and FrankKi MCPConnect Hermes Agent to FrankKi MCP. Prepare a physical letter, check the preview and postage quote, and approve the letter before dispatch.Send physical letters with OpenClaw and FrankKi MCPSet up FrankKi as an OpenClaw MCP server. Check authentication and tool access, prepare a letter, and review the postage quote before approval.When to put a complaint or request in writingA practical way to decide when a dated letter helps, what evidence to keep, and which US or UK template fits the problem.Send a letter from an AI agent in a minute, with no accountFrankKi runs a public MCP lane with no sign-in: seven tools, three calls, one Stripe link. The full walkthrough with real production output, the prices, and the rules the lane enforces in code.
Ready?
Write your first letter.
For everything that belongs on paper. Written in the browser, from a template or by your AI assistant, delivered worldwide.
Connect FrankKi to your AI agent
Choose your app. Below you see how to set up FrankKi there.
How to add FrankKi in Claude
Anthropic's guide (opens in a new tab)In Claude, open Customize > Connectors.
Click + Add, then Add custom connector.
Name it FrankKi, paste this URL and click Continue.
https://mcp.frankki.appKeep the detected settings and click Continue. Under Authentication choose Sign in now, then click Add.
In the window that opens, sign in with your FrankKi account or create one. New accounts get a code by email, which you enter. If you have not signed the data processing agreement yet, you sign it here. Then allow access.
Claude Team or Enterprise: an owner adds it once under Organization settings > Connectors (Add, then Custom > Web). Everyone else clicks Connect on it under Customize > Connectors.
Then: Claude sets up FrankKi
This is a plain message to Claude. It tells Claude what to set up, and that nothing is sent or paid for without your approval. Send it in a new chat once FrankKi is connected.
Setup promptConnect FrankKi at https://mcp.frankki.app so we can send letters by post. Ask me before you connect or grant permissions. Then run the FrankKi connection check mcp_health to see what my account still needs, and walk me through the setup step by step. Take our sender details and brand from our website and ask me once before you save them. Copy 1 to 3 templates that fit my business and show me one preview. For steps only I can do, such as a top-up, give me the link. Without my approval you send nothing and pay for nothing. Never switch on autopilot yourself.