Individuals who are blind and use screen readers face challenges in obtaining a quick overview of numerical data in tables because they must navigate cell by cell, listening to the individual values. The demands on working memory can quickly exceed available capacity, slowing the user’s speed in solving problems involving patterns or trends in the data. We developed a web standards-based, cross-browser sonification tool that allows users to hear entire columns (or rows) of numbers as a quick succession of tones. After thus obtaining an overview of the data, the user can then zoom in to examine specific values, using a screen reader. Such a capability was expected to be valuable to users of screen readers who are blind. We also report on a small-scale evaluation of the user interface of the tool by adult screen reader users (N = 7) in the context of realistic science assessment tasks involving time series data. The majority of the participants in this evaluation expressed agreement with statements asserting that the sonification capability was easy to use, easy to learn to use, and useful. Areas for future development include enhancements to the keyboard interface and to the user instructions.