GuidesWhat is iXBRL (and why you don’t need to worry about it)

What is iXBRL (and why you don’t need to worry about it)

iXBRL is a technical requirement that deters many owners from filing themselves. In practice, with the right software you never deal with it directly. Here is what it is.

iXBRL in brief

iXBRL is a way of labelling the figures in your accounts so that software can read them as reliably as a person can. The document looks the same; each figure carries a tag behind the scenes.

HMRC and Companies House require accounts and tax computations in this format so their systems can process your figures automatically.

Why it matters to you

Producing iXBRL by hand would mean tagging every figure correctly — slow, error-prone, and a common reason filings are rejected.

OneFiler generates all the iXBRL automatically, using the formats HMRC currently accepts. You only ever see your figures; the tagging happens behind the scenes.

Common questions

Do I need to buy separate iXBRL software?

No. OneFiler generates the iXBRL for your accounts and tax computation as part of the filing — there is nothing separate to buy or learn.

Is iXBRL the same as XBRL?

They are closely related. XBRL is the underlying data standard; iXBRL (“inline XBRL”) embeds those tags inside a normal, human-readable document, which is what HMRC and Companies House require.

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