How do you calculate accuracy on a running record?

Subtract the errors from the total words read, divide by the total words, and multiply by 100. Reading 200 words with 10 errors gives (200 - 10) / 200 x 100, an accuracy rate of 95%. Texts at 95% to 100% are considered easy or independent level, 90% to 94% instructional, and below 90% hard or frustration level.

What is a good self-correction ratio?

The self-correction ratio is errors plus self-corrections, divided by self-corrections. A ratio of 1:3 or better, meaning the reader corrects at least one in every three miscues, shows the child is monitoring their own reading. With 10 errors and 5 self-corrections the ratio is (10 + 5) / 5, which is 1:3.

What do the three reading levels mean?

Easy or independent (95% to 100% accuracy) suits independent reading. Instructional (90% to 94%) is the sweet spot for guided teaching, challenging but manageable with support. Hard or frustration (below 90%) means the text is too difficult and a simpler one will teach more.

Running Record Calculator

This running record calculator does the conversions teachers otherwise look up in tables: enter the total words read, the number of errors and the number of self-corrections, and it returns the accuracy rate, the error ratio, the self-correction ratio and the reading level. Running records are the standard way New Zealand primary teachers assess oral reading, following Marie Clay's conventions, and the arithmetic is fiddly enough at the end of a busy listening session that a quick calculator earns its place. The accuracy rate places the text for that child: 95 percent and above is easy or independent level, 90 to 94 percent is instructional, the level where guided teaching works best, and below 90 percent the text is hard, or frustration level, and will teach less than an easier book. The error ratio expresses how often a miscue occurs, one error in every so many words, while the self-correction ratio shows how actively the child is monitoring their own reading, with one in three or better generally regarded as strong self-monitoring. Use it after any running record, from PM Benchmark and probe assessments through to informal records on classroom texts, and record the three figures straight into your notes.

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Total words read

Errors

Self-corrections

95%

accuracy — easy / independent level

Error ratio1:20

Self-correction ratio1:3

LevelEasy

Self-corrections are not counted as errors. Accuracy is shown to one decimal place where needed; ratios are rounded to one decimal place. Conventions follow Marie Clay's running record scoring.

Reading levels at a glance

Accuracy	Level	Best used for
95% – 100%	Easy / independent	Independent reading, fluency and enjoyment
90% – 94%	Instructional	Guided reading and teaching new strategies
Below 90%	Hard / frustration	Too difficult; choose an easier text

How it works

Accuracy is the words read correctly divided by the total words, as a percentage: (words - errors) / words x 100. The error ratio divides total words by errors to give one error in every so many words. The self-correction ratio is (errors + self-corrections) / self-corrections, read as one self-correction for every so many opportunities; a ratio of 1:3 or better suggests the reader notices when meaning breaks down and fixes it. The level comes straight from the accuracy rate using the standard bands in the table above.

Worked example

A child reads a 200 word text with 10 errors and 5 self-corrections. Accuracy is (200 - 10) / 200 x 100, which is 95%, right on the easy or independent boundary. The error ratio is 200 / 10, or 1:20, one error in every 20 words. The self-correction ratio is (10 + 5) / 5, which is 1:3, so the child fixed one in every three miscues, a strong sign of self-monitoring. Together the record suggests the text is comfortable and the next step up would sit in the instructional band.

Related calculators

Reading Age Calculator: estimate reading age.
Reading Time Calculator: how long a text takes.
Grade Calculator: weighted course grades.
Test Score Percentage Calculator: marks to percentages.

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