IRF is a three-letter acronym that stands for:
- Immature Reticulocyte Fraction
- Impulse response function
- Incident Reporting Form
- Information Retrieval Facility
- Initial Reaction Force or Immediate Response Force
- Inpatient Rehabilitation Facility
- Institute of Space Physics (Sweden)
- Instructional Reform Facilitator (San Francisco Unified Schools)
- Intelligence Records Facility
- Interchange Reimbursement Fee
- Interest Rate Future
- Interference Rejection Factor
- Interferon Regulatory Factor (e.g. IRF6)
- International Rectifier
In foundations/organizations:
- International Rabbinic Federation
- International Ranger Federation
- International Road Federation
- International Rogaining Federation
- Iran Research Foundation
- Islamic Research Foundation
In computing:
- Intelligent Resilient Framework, Virtual Switch Chassis Aggregation
- Inherited Rights Filter, a logical access constraint in Novell NetWare