MARCReady — Supported File Formats
Supported input and output formats for MARCReady MARC repair.
MARCReady accepts catalogue data in a range of formats and exports records in the standard MARC formats used across library systems. This page lists all supported input and output formats.
See the MARCReady overview for a general introduction to what the tool does.
Supported input formats
| Format | Extension(s) | Best for |
|---|---|---|
| MARC21 Binary | .mrc, .marc | Existing ILS exports and vendor MARC files |
| MARCXML | .xml, .marcxml | XML-based exports and system integrations |
| MRK (MARC Breaker) | .mrk | MARCEdit workflows |
| CSV | .csv | Spreadsheet-based catalogue cleanup |
| TSV | .tsv | Tab-separated exports from legacy systems |
| Excel | .xlsx, .xls | Spreadsheet-based catalogue cleanup |
| JSON | .json | Structured exports from custom systems |
Supported output formats
| Format | Extension | Notes |
|---|---|---|
| MARC21 Binary | .mrc | Standard format for library systems and tools |
| MARCXML | .marcxml | Library of Congress standard XML encoding |
Koha’s Stage MARC Records for Import tool, as well as most other library systems, accept both output formats.
Notes on CSV, Excel, TSV, and JSON input
When you upload a spreadsheet, delimited file, or JSON export, MARCReady can help convert structured files to MARC21 after you review the proposed mapping. Kai analyses column headers or JSON fields and proposes a mapping from each to a MARC field and subfield. This mapping is presented for your review before any records are processed.
A few things to keep in mind:
- You review the mapping before export. Kai’s suggestions are a starting point. You can adjust any field assignment before records are written.
- Mapping quality depends on column header clarity. Columns with descriptive headers (e.g. “Author”, “ISBN”, “Subject”) map more reliably than columns with generic names (e.g. “Field1”, “Column A”).
- No structured MARC data is assumed. Each row in the spreadsheet is treated as a single bibliographic record.
If your spreadsheet was exported from a legacy system with a non-standard layout, it is worth reviewing the mapping carefully before proceeding.
File size limits
MARCReady supports uploads up to 200 MB per file.
- Small files (≤ 6 MB) — uploaded via the standard multipart form
- Large files are handled securely — Larger files are uploaded securely using a direct upload process designed for files up to 200 MB.
Most library catalogues fit comfortably within this limit. For institutions with very large catalogues (millions of records), we recommend splitting the export into multiple files. Contact KohaSupport if you need assistance planning large uploads.
Character encoding
UTF-8 files are recommended. MARCReady can detect and normalise some common legacy encoding issues, but heavily corrupted files may still require manual review.
Output formats
MARCReady exports standard MARC21 binary and MARCXML. These are the expected formats for Koha’s staged record import workflow and are compatible with most other library systems that accept standard MARC files.
Next Steps
More in Resources & Guides
Was this article helpful?