ObCalc
OB/MFM Clinical Calculators
$6.99 · Designed for iPad. Not verified for macOS.
ObCalc puts the calculators, scoring tools, and reference charts that obstetrics, maternal-fetal medicine, and labor & delivery teams reach for every shift into one fast, offline-first app.
Every formula is sourced to published guidelines (ACOG, SMFM, CMQCC, NICHD) and built as a clinical tool first — clean inputs, clear interpretation, no clutter.
OBSTETRICS
• Bishop Score
• Estimated Due Date — LMP, ultrasound, conception, ovulation, or IVF transfer dating
• Pregnancy Re-dating (ACOG Committee Opinion 700)
• Pregnancy Weight Gain Tracker
• Urine Protein:Creatinine Ratio (UPCR)
• VBAC Success Calculator — Grobman MFMU model
• VBAC at Delivery Admission Success Calculator — Grobman MFMU model
PERINATOLOGY / MFM
• CVR (CPAM Volume Ratio)
• Extremely Preterm Birth Outcome (NICHD)
• Fetal Biometry Suite — Hadlock EFW, long-bone ratios, multi-panel z-scores and percentiles
• Intrauterine Transfusion (IUT) Volume Calculator
• MCA Doppler / PSV for Fetal Anemia
• Neonatal Morbidity Risk
• Ponderal Index
• GDM Insulin Dosing
• Life-Limiting Skeletal Dysplasia Screen
• Twin Discordance
• Umbilical Artery Doppler
GENERAL
• Anion Gap • Apgar Score • BMI • Iron Deficit • Peak Flow
• Gestational Age (date difference)
• Maternal Sepsis Assistant (qSOFA / Sepsis-3)
• CMQCC Sepsis Screen
THROMBOPHILIA
• VTE Anticoagulation Dosing (ACOG Practice Bulletin 196)
GENETICS
• cfDNA PPV/NPV Calculator
• Nuchal Translucency Percentile
WHY CLINICIANS CHOOSE OBCALC
• Offline-first — no connection needed on L&D
• Fast, distraction-free interface — no ads, no tracking
• One-time purchase. No subscription, no account required
• Regularly updated with new tools and guideline changes
• Built-in unit conversion and inline number-pad arithmetic on every input
ObCalc is a clinical reference tool intended for use by licensed healthcare professionals. It does not replace clinical judgment, and results should be confirmed against current guidelines and your institution's protocols.
Ratings & Reviews
- This app’s overall rating was recently reset.
Added minor improvements and acknowledgements
The developer, Code Nine Labs LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Code Nine Labs LLC
- Size
- 3 MB
- Category
- Medical
- Compatibility
Requires iOS 26.0 or later.
- iPhone
Requires iOS 26.0 or later. - iPad
Requires iPadOS 26.0 or later. - Mac
Requires macOS 26.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 26.0 or later.
- iPhone
- Languages
- English
- Age Rating
16+
- 16+
- Frequent
Medical Treatment information
- Copyright
- © Code Nine Labs, LLC

