Cleanter Developer Docs

Cleanter is an Android app that lets your web app print to a Bluetooth thermal receipt printer. Your page sends JSON over local HTTP; Cleanter turns it into ESC/POS commands and prints. No SDK, no driver, no cloud.

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New here? Start with the Quickstart to get a receipt printing in about five minutes, then skim the HTTP API reference for every field you can send.

Explore the docs

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Quickstart

Install, pair a printer, start the server, and print your first receipt.

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Try the builder

Build a receipt visually on the homepage and copy the generated JSON.

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HTTP API

Every endpoint, field, content block, and response — the full reference.

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Troubleshooting

Fix the common snags: mixed content, 503s, garbled characters, detection.

How it works

Cleanter runs a small HTTP server on the Android tablet, bound to localhost only. Anything on the same device — usually a web app open in Chrome — sends it a print job. The flow is:

Because the server is localhost-only, the web app and Cleanter must run on the same tablet. It is never reachable from your network or the internet.

At a glance

Base URL	`http://localhost:9100`
Endpoints	`GET /health`, `POST /print`
Payload	`application/json` — an array of content blocks
Paper widths	80 mm (48 chars) and 58 mm (32 chars)
Printers	Bluetooth Classic (SPP) ESC/POS — paired in Android settings