AI Translation Quality (BLEU/TER)
Compare translation quality metrics BLEU, TER, and Human Eval to estimate post-editing effort. Enter values for instant results with step-by-step formulas.
Worked Examples
Example 1: High-Quality Neural Output
Problem: BLEU: 65, TER: 15, Human: 4.8/5
Solution: Score = (65×0.4) + (85×0.3) + (96×0.3) = 26 + 25.5 + 28.8 = 80.3
Result: 80.3 (Excellent)
Example 2: Raw Statistical MT
Problem: BLEU: 25, TER: 60, Human: 2.5/5
Solution: Score = (25×0.4) + (40×0.3) + (50×0.3) = 10 + 12 + 15 = 37.0
Result: 37.0 (Poor)
Frequently Asked Questions
What is a good BLEU score?
A BLEU score between 40-50 is generally considered high quality for machine translation, often comparable to human translation. Scores above 60 are very rare and may indicate overfitting. Scores below 20 usually mean the translation is barely understandable.
How does TER differ from BLEU?
BLEU measures similarity to a reference (higher is better), while TER (Translation Edit Rate) measures the amount of editing needed to fix the output (lower is better). TER is more directly correlated with post-editing effort.
Is BLEU score percentage or decimal?
It can be both. We use 0-100 scale here for simplicity, but research papers often use 0.0-1.0. A score of 45 here equals 0.45 in decimal notation.
How accurate are the results from AI Translation Quality (BLEU/TER)?
All calculations use established mathematical formulas and are performed with high-precision arithmetic. Results are accurate to the precision shown. For critical decisions in finance, medicine, or engineering, always verify results with a qualified professional.
How do I get the most accurate result?
Enter values as precisely as possible using the correct units for each field. Check that you have selected the right unit (e.g. kilograms vs pounds, meters vs feet) before calculating. Rounding inputs early can reduce output precision.
Does AI Translation Quality (BLEU/TER) work offline?
Once the page is loaded, the calculation logic runs entirely in your browser. If you have already opened the page, most calculators will continue to work even if your internet connection is lost, since no server requests are needed for computation.