# Pure NMR — NMR Impurity Reference Guide

> NMR Impurity Reference Guide (iPhone/iPad app by Marcal Casas Cartagena.)

- Source: https://appshunter.io/ios/app/pure-nmr/id482490330 (this page in markdown: same URL + `.md`)
- Developer: [Marcal Casas Cartagena](https://appshunter.io/developer/468150889)
- Category: Education, Utilities
- Price: Free (on sale, was $2.99)
- Age rating: 4+
- Requires: iOS 26.1 · 5 MB
- Languages: American English
- Released: 2011-11-29
- Data updated: 2026-05-19
- User reviews in markdown: https://appshunter.io/ios/app/pure-nmr/id482490330/reviews.md

## What is Pure NMR?

Pure NMIdentify NMR impurities instantly with Pure NMR.
Pure NMR is the essential reference tool for chemists working with NMR spectroscopy. Quickly identify unknown peaks in your ¹H and ¹³C spectra by searching a comprehensive database of common laboratory impurities and residual solvents.

FAST & ACCURATE SEARCHES

Enter a chemical shift value and instantly find all matching impurities within your specified tolerance range. Search across multiple deuterated solvents including CDCl₃, DMSO-d₆, CD₃CN, D₂O, and more.

COMPREHENSIVE DATABASE

Access chemical shift data for over 60 common impurities including:

Residual solvents (water, acetone, ethyl acetate, etc.)
Common reagents (triethylamine, acetic acid, TMS, etc.)
Laboratory contaminants (silicone grease, pump oil, etc.)
Stabilizers and additives (BHT, BHA, etc.)

All data is based on peer-reviewed literature (Fulmer et al., Organometallics 2010; Gottlieb et al., J. Org. Chem. 1997).

KEY FEATURES

- Search by chemical shift (1-H or 13-C)
- Adjustable tolerance range (0.0 to +/-1.0 ppm)
- Support for 14 deuterated solvents
- View complete assignment information (multiplicity, coupling constants)
- Add your own custom impurities to the database
- Browse all impurities by solvent
- Dark mode support
- Customizable interface colors
- No internet connection required - fully offline

PERFECT FOR

Organic chemists characterizing compounds
Graduate students learning NMR spectroscopy
Research scientists in academia and industry
Anyone who needs quick impurity identification

SCIENTIFICALLY VALIDATED

All chemical shift values are sourced from authoritative scientific publications, ensuring accuracy and reliability for your research.

EASY TO USE

Select your nucleus (1-H or 13-C)
Choose your deuterated solvent
Enter the unknown chemical shift
Get instant results with full spectroscopic details

Stop flipping through reference books or searching online databases. Pure NMR puts all the essential impurity data right at your fingertips.

PRIVACY FOCUSED

Pure NMR works completely offline. No data collection, no tracking, no internet required. Your searches stay on your device.You can also custom save the Default conditions so that every time the App starts up, you are ready to go without having to select them again.


## Version history (last 4 releases)

### 3.1 — 2026-02-22

Improvements done on the database first loading.

### 3.0 — 2025-12-01

Pure NMR 3.0 - The Complete Redesign

After 13 years, Pure NMR is back with a massive update! Version 3.0 is a complete rebuild for modern iOS.

WHAT'S NEW

Beautiful Modern Interface

Complete visual redesign
Dark Mode support
Custom color themes
Optimized for latest devices

Powerful New Features

Add custom solvents and nuclei
Advanced sorting options
Protected built-in database
Enhanced search capabilities
Set default preferences

Full Customization

Unlimited custom impurities
Manage your personal database
Keep custom data separate from built-in reference

Performance & Polish

Rebuilt with SwiftUI and SwiftData
Faster, more responsive
Better iPad support
Fully offline, completely private

The trusted scientific data you rely on, now with the modern features and interface you deserve.

### 2.0 — 2012-07-23

- Optimized search algorithm
- Ability to search all entries for a given solvent.
- Ability to delete database entries.
- Ability to search among all the impurities.
- Ability to search among all the assigments.
- Optimized "Save Custom" input (less typing).
- Minor User Interface optimizations.

NEW: Native iPad support !!!

### 1.0 — 2011-11-29

No release notes.

## More apps by Marcal Casas Cartagena

- [Concentrations](https://appshunter.io/ios/app/concentrations/id468150886)
- [Pano Assist](https://appshunter.io/ios/app/pano-assist/id532997023)
- [Erasmus Tracker](https://appshunter.io/ios/app/erasmus-tracker/id6758699184)

All apps by Marcal Casas Cartagena: https://appshunter.io/developer/468150889

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-05-19.*