Tools · nothing uploaded
Build a message, look something up
Generate a sample message to work from, look up a code set, or see what the standard contains. Already have a message to check? The workspace does that in one step.
Everything runs locally. Your messages never leave this tab.
The engine loads automatically when you start using a tool.
Generate a message
Synthetic messages with valid identifiers and rail-appropriate defaults. Useful for testing pipelines without real payment data.
External code sets
Return reasons, payment purposes, transaction statuses and balance types. Search by code, name, or description.
The published standard
Message definitions by business area, across every message set the Registration Authority publishes.
askiso catalog add ~/Downloads/<set>.zip.
This is not the official ISO 20022 site. The sole source of up-to-date material is iso20022.org.
About these tools
What these tools are for
These three cover what the workspace deliberately does not. The workspace answers questions about a message you already have. These help when you have not built one yet, or when the question is about the standard itself.
Everything runs inside your browser, on the same engine as the command line. Nothing you enter is ever uploaded.
Generate a sample message
Generating a message is how most integrations begin. You need something structurally correct to send through a pipeline before genuine data exists, and composing one manually from a schema is slow and error-prone.
Select a message type and AskISO constructs one. Where a template exists the result is realistic. Where none exists, AskISO traverses the schema instead and produces something minimal and synthetic. It identifies which of the two you received, because a synthetic message is adequate for assembling a pipeline and misleading as an example of genuine traffic.
Look up a code set
ISO 20022 refers to external code sets by name rather than listing their values in the schema. That is efficient for the standard and awkward in practice: the schema establishes that a field holds a code, but never which particular codes are permitted.
This searches the code sets AskISO carries, so you can verify a value without opening a specification document. The origin of each code appears alongside it.
See what the standard contains
The standard is larger than most people expect, and its shape is hard to picture from a list. This shows the distribution: how many definitions each business area publishes, and how many versions sit behind them.
It is genuinely useful for scoping an implementation. "We support ISO 20022" means something different for payments, where a handful of messages cover most traffic, than for securities, where the catalogue runs to hundreds.
Checking a message you already have
Use the workspace instead. Paste the message and it identifies what you provided, then lints it, applies the November 2026 requirements, and validates it against your own schemas whenever you have selected a catalogue.
Some of that was possible here too, which meant two interfaces to learn and no clear way to tell which one to open. There is now one.