FIXCraft — Parse. Edit. Validate.

Inspect, edit, validate, and regenerate FIX protocol messages entirely in your browser.

FIXCraft is a local-first workspace for developers and production-support engineers who work with Financial Information eXchange (FIX) protocol messages. Paste an existing FIX message or start with a basic protocol template. FIXCraft turns the message into an editable, searchable field table backed by standard FIX XML data dictionaries. Key capabilities: • Parse SOH, \x01, <SOH>, and pipe-delimited messages • Display tag numbers, standard field names, values, and descriptions • Edit, add, reorder, and remove fields while protecting BeginString (8), BodyLength (9), and CheckSum (10) • Recalculate BodyLength and CheckSum automatically • Identify supplied BodyLength and CheckSum mismatches • Display header, body, repeating groups, nested groups, and trailer fields clearly • Support FIX 4.2, FIX 4.4, and FIXT 1.1 • Search by tag number or field name • Generate output using SOH or pipe delimiters • Copy or download regenerated messages • Save reusable templates in browser-local storage • Switch between light and dark themes FIX messages can contain sensitive operational or trading data. FIXCraft processes messages locally in your browser and does not transmit FIX content to an external server.