Inclusion Criteria:  Age 18-75 years Type 1 diabetes ≥2 years. HbA1c >=58 mmol/mol Insulin pump treatment ≥12 months CGM or isCGM use ≥6 months Novorapid use ≥4 weeks Carbohydrate counting and use of the insulin pump bolus calculator for most snacks and meals. Carbohydrate intake >80 grams per day (assessed by review of intake recorded in the insulin pump during the 2 weeks prior to the screening visit)  Exclusion Criteria:  Breast-feeding, pregnancy or planning to become pregnant. Use of anti-diabetic medicine (other than insulin), corticosteroids or other drugs affecting glucose metabolism during the study period or within 30 days prior to study start. Use of hybrid closed-loop systems Daily use of paracetamol (acetaminophen) Alcohol or drug abuse. Severe cardiac disease or retinopathy contraindicating HbA1c <53 mmol/mol. Other concomitant medical or psychological condition that according to the investigator's assessment makes the person unsuitable for study participation. Lack of compliance with key study procedures at the discretion of the investigator. Unacceptable adverse events at the discretion of the investigator.