CER/WER Diff Viewer

Compare two texts and inspect character- and word-level differences.

About this tool

Forget confusing diff outputs. Our tool visualizes the Levenshtein distance with an intuitive, color-coded system to give you an at-a-glance analysis.

  • DELYellow on Hypothesis line — deletions from the Reference.
  • INSGreen on Reference line — insertions present in Hypothesis.
  • SUBWhite on marker line — substitutions between Reference and Hypothesis.

Built for CJK, perfect for all text. This visual analysis is powered by flawless CJK alignment with a fixed-width Unicode font, ensuring Chinese, Japanese, and Korean characters stay perfectly aligned. No more broken comparisons—get accurate, intuitive visual diffs for evaluating CER/WER in ASR, OCR, and text-processing models.

Inputs

About Inputs

Paste your reference (ground truth) and hypothesis (prediction). Use Multi-line mode to join lines and compute a single score across the whole text.

Reference (Ground truth)

Hypothesis (Prediction)

CER/WER Metrics

About Metrics

Character Error Rate (CER) and Word Error Rate (WER). Lower is better.

ScopeCER distance (ratio)WER distance (ratio)Details

Alignment Visualization

How to Read

Three-line view: Reference (top), Hypothesis (middle), and a marker line (bottom). Green squares on the Reference indicate insertions; yellow squares on the Hypothesis indicate deletions; white squares on the marker line indicate substitutions.