FlowHeater – the data specialist for lean data integration

FlowHeater is developed and distributed by FlowHeater GmbH – with a clear philosophy: Because simple is more productive. Since April 1, 2009, we have been developing software that solves a very specific problem: Companies need to reliably move data between systems, prepare it, and adapt it to target structures – without turning it into a separate development project every time.

In practice, you rarely encounter clean data worlds. Instead, there are CSV and Excel files from specialist departments, XML or JSON structures from interfaces, databases from ERP/CRM systems, or REST APIs from cloud services. This is exactly where FlowHeater comes in: as a pragmatic tool for data integration, data migration, import/export, and data mapping – understandable, visual, and repeatable.

Why is FlowHeater available?

Many data integration and ETL tools established on the market are powerful – but often also cumbersome: lengthy setups, extensive configurations, steep learning curves, and overhead that unnecessarily slows down the process of “quickly building a data flow.”

FlowHeater was deliberately developed as a lean, ready-to-use tool. You download the ZIP archive, unzip it, and start the Designer – installation is not mandatory, but an optional setup is available. After a short training period, supported by examples and documentation, you will be able to implement even complex transformations with confidence.

From the outset, it was important to us that FlowHeater remain consistently simple. That's why we don't focus on an additional layer of standards and meta-configurations. XML, for example, is primarily used as a storage format for definitions – not as a technology that you have to think about in your everyday work.

The philosophy: visual, understandable, repeatable

FlowHeater works with definitions: you create data flows graphically, test them, save them for reuse, and execute them again later in exactly the same way – manually, in batches, or automatically in server mode. This makes processes traceable and reduces errors that would otherwise occur if the same transformation were to be recreated ad hoc over and over again.

The Visual Designer is deliberately designed to help you achieve results quickly: fields are connected using drag & drop, rules are added in the appropriate places, and the logic remains readable even months later – for you and your team.

How FlowHeater works – in clear building blocks

A FlowHeater process is easy to explain: data is read from a source, structured internally, transformed according to your rules, and then written to the target system. FlowHeater uses a few clear building blocks to do this:

• Adapters: Interfaces through which FlowHeater reads data from sources and outputs it to targets – e.g., text/CSV, Excel, XML, JSON, Access, SQL Server, MySQL/MariaDB, PostgreSQL, SQLite, Oracle, ODBC/OleDB, or REST.
  
  
• Pipes: Visual links between fields that you can use to build your mapping via drag & drop.
  
  
• Heaters (functions): Transformation modules for the actual data preparation – such as combining texts, calculating values, changing date formats, applying rules/filters, creating files, or enriching data records.
  
  
• Fitter: The central logic that automatically performs the necessary conversions so that data types, target formats, and typical special cases do not become tedious work.

Data quality, formats, and encodings – without headaches

In real-world projects, data integration rarely fails because of the basic idea, but rather because of details: different date formats, decimal separators, special characters, code pages, or mixed Unicode variants.

FlowHeater is designed to overcome these hurdles in everyday use. You can convert data between different locale settings (e.g., German date format → English date format) and work with many encodings/code pages – even in combination. This keeps your process stable, even if the source and target do not speak the same language.

Why the name FlowHeater?

The name was deliberately chosen to be descriptive: like a flow heater, FlowHeater processes data as it flows through—it is continuously read, checked, and converted as it flows through the processing chain. The terms used in the product are also derived from this idea: Adapters as connections, pipes as links, heaters as function modules, and the fitter as the assembler at the center of the process. This is not just a play on words, but a model that is quickly understood from a technical perspective.

From migration to automation

FlowHeater is equally suited to one-off tasks and recurring routines:

• Designer: Create, test, and document definitions.
  
  
• Batch module: Execute definitions automatically and on a schedule – ideal for regular exports, imports, or nightly jobs.
  
  
• FlowHeater Server: Optional operation as a Windows® service – time- or event-triggered, e.g., via directory monitoring (“new file found → start job”) or according to a schedule. This means that processes run even when no user is logged in.

And if things get really specific: For individual special logic, definitions can optionally be extended using the .NET Script Heater (C# / VB.NET). This means that FlowHeater can be used without programming in standard cases – and is still flexible when needed.

Just get started – and grow cleanly

To get started, there is a freeware version that allows you to quickly get to know FlowHeater without registering. This allows you to quickly check whether the operating philosophy, the variety of adapters, and the transformation options meet your requirements.

If the trial turns into productive use, licenses and optional modules are available – without any disruption to your workflow: your definitions remain usable and scale with your requirements.

FAQ

What data sources and targets does FlowHeater support?

The most important adapters include Text/CSV, Excel, XML, JSON, Access, SQL Server, MySQL/MariaDB, PostgreSQL, SQLite, Oracle, ODBC, OleDB, and many more, as well as REST API (additionally including InMemory and TestData). All adapters can be combined and are included in the standard delivery.

Do I need programming skills to use FlowHeater?

No. Mapping and transformation are performed in the Visual Designer without code. Programming skills are not required. For special cases, the .NET Script Heater (C# / VB.NET) is available as an option.

Can FlowHeater process large amounts of data?

Yes. There is no fixed limit for records/fields/Heaters. The theoretical upper limit is approximately 2 billion rows – in practice, the database, RAM, and runtime are more likely to impose limits.

On which systems does FlowHeater run?

FlowHeater runs on Windows® 10/11 and Windows® Server 2016/2019/2022/2025. The prerequisite is .NET Framework 4.8 (plus hardware requirements such as at least 8 GB RAM).

What does the freeware version include?

• Free, process up to 100,000 records (max.)
• Restrictions: stored definitions after opening max. 50 records; when using heaters/functions also max. 50 records

What license models are available?

• Freeware
  
  
• Single-user licenses (e.g., Designer, Designer+Batch, Runtime Designer)
• Company licenses (including Runtime Designer company license; authorization to install at the site)

Prices for licenses start at €89 (depending on the license).

Are there updates for FlowHeater and how long are they available?

Once you have purchased a license, you can use the software permanently. Depending on the license, updates are included for 1 year or 3 years. After that, you can continue to use FlowHeater – but without entitlement to new versions.

Update extensions are possible (with a 30% discount), but only if the license has not expired for more than 3 months. In addition, beta versions are released approximately every 2 weeks (including update notifications in the Designer).