The same numerical pair can pass one text reference and fail another because WCAG distinguishes conformance level and text category. A calculator can compare the ratio with each threshold, but it cannot know whether the rendered text qualifies as large or whether an exception applies.
Normal text uses 4.5:1 for AA and 7:1 for AAA
For ordinary text, ContrastCheck reports AA pass at a raw ratio of at least 4.5 and AAA pass at at least 7. These are minimum boundaries, not targets that guarantee comfortable reading for every person, display, font or condition. A result of 4.49 fails AA normal even when another formatter could round it to 4.5; the raw calculation remains authoritative.
Large text uses 3:1 for AA and 4.5:1 for AAA
Large text has lower numerical references because size and weight affect legibility. The WCAG definition depends on rendered size and boldness rather than a label chosen in this tool. ContrastCheck deliberately shows both rows and never infers which one applies. Verify the actual CSS, font metrics, zoom behavior and content presentation before treating the large-text row as relevant.
A threshold row is not a conformance report
A page includes hover, focus, disabled and visited states; text can cross images, gradients and changing backgrounds. It also has non-text controls, focus indicators, alternative content and many requirements unrelated to contrast. Use this pair result as one measured input to a broader review. Do not describe a website as WCAG, legally or accessibility compliant solely because entered colors pass.