SMV/Acidity Calculator

Map any sake on the four-quadrant taste profile chart using Sake Meter Value (nihonshu-do) and acidity (san-do). Input SMV and acidity values to visualize where the sake falls on the light-rich and dry-sweet axes. Includes amino acid level for a three-dimensional taste prediction.

Calculator

Tool

Sweet (-15) Dry (+15)
Light (0.5) Full (3.0)
Kunshu
薫酒
Fragrant & Light
Soushu
爽酒
Refreshing & Light
Jukushu
熟酒
Rich & Sweet
Junshu
醇酒
Rich & Dry
Light Body
Full Body
Sweet
Dry

How to Use

  1. 1
    Enter the Sake Meter Value (SMV)

    Input the nihonshu-do (日本酒度) printed on the bottle's back label — positive values (e.g., +5) indicate drier sake; negative values (e.g., -3) indicate sweeter sake.

  2. 2
    Enter the san-do acidity value

    Input the san-do (酸度) value, typically between 1.0 and 2.0, which measures titrated acidity; higher acidity contributes a perceived dryness and body that modifies the SMV's dry-sweet impression.

  3. 3
    Read the four-quadrant taste profile

    Interpret your sake's position on the dry-sweet and light-full body matrix, then use the accompanying flavor and food-pairing suggestions to guide your serving choice.

About

The SMV/Acidity calculator operationalizes two of the most important technical parameters printed on sake labels, translating raw numbers into a practical flavor and pairing roadmap. The nihonshu-do (SMV) was developed in post-war Japan as a standardized metric for the sake industry, giving distributors and retailers a consistent vocabulary for describing sake's dry-sweet axis at a time when regional sake styles varied enormously.

The key insight behind the four-quadrant system is that neither SMV nor san-do alone is sufficient to predict flavor. SMV measures sugar density as a proxy for sweetness, while san-do measures total acidity, which physically suppresses sweetness perception on the palate through competitive inhibition of sweetness receptors and provides a textural sense of body. A sake with SMV -2 (technically sweet) but san-do 2.0 (high acid) can taste surprisingly dry and full-bodied — classified as junshu (醇酒) on the four-quadrant map. Conversely, a sake with SMV +5 (dry) but san-do 0.9 (very low acid) can taste softer and rounder than the number implies.

For practical consumers and food-pairing enthusiasts, the four-quadrant matrix — kunshu, soushu, junshu, jukushu — provides a memorable framework for navigating stylistic diversity. Japanese sake sommeliers (kikizake-shi), certified by the Sake Service Institute, use this framework as a core tool in their curriculum. Understanding these axes transforms label reading from guesswork into a reliable predictor of the drinking experience awaiting inside the bottle.

FAQ

What does the Sake Meter Value (SMV) measure?
The Sake Meter Value, or nihonshu-do (日本酒度), is a hydrometric measure of the specific gravity of sake relative to water at 4°C. Pure water registers 0; sake with dissolved sugars is denser than water, producing a negative SMV (sweeter); sake with higher alcohol content and less residual sugar is less dense, producing a positive SMV (drier). The scale typically runs from approximately -10 (very sweet) to +10 (very dry), though extreme examples exist. A sake labeled +3 is considered moderately dry; -3 moderately sweet. Importantly, SMV alone is insufficient to predict flavor — two sakes with identical SMV can taste very different depending on their acidity levels.
How does san-do (acidity) affect perceived taste?
San-do measures the total titrated acidity of sake, expressed as the milliliters of NaOH solution required to neutralize the acids in a 10ml sake sample. The primary acids in sake are succinic acid (琥珀酸), lactic acid (乳酸), and malic acid, with smaller amounts of citric and pyroglutamic acids. Higher acidity creates a perception of dryness, body, and sharpness that can counteract residual sweetness — a sake with negative SMV but high san-do may taste drier than expected. Conversely, low-acid sake with a positive SMV can taste soft and even slightly sweet despite the dry measurement. Kimoto and Yamahai sakes typically show san-do values of 1.7–2.2, contributing their characteristic robust body.
What is the four-quadrant sake flavor matrix?
Japanese sake educators developed a four-quadrant taste map by plotting SMV (dry-sweet axis) against san-do (light-full body axis). The four resulting regions characterize common style types: kunshu (薫酒, fragrant and light — low SMV positive, low acid, typical of Ginjo and Daiginjo), soushu (爽酒, refreshing and light — positive SMV, low acid, typical of light Junmai), jukushu (熟酒, rich and full — negative SMV, high acid, typical of aged koshu), and junshu (醇酒, rich and dry — positive SMV, high acid, typical of Kimoto Junmai). This system was formalized by sake educator Haruo Matsuzaki and is widely used in Japanese sake sommelier (kikizake-shi) certification curriculum.
Why do two sakes with the same SMV taste different?
SMV captures only sugar-derived density and says nothing about the concentration and type of acids, amino acids, or specific flavor compounds. San-do (acidity) modifies the sweet-dry perception significantly, while amino acid content (measured separately as amino-do, 아미노산度) contributes savory umami depth. Yeast strain selection further determines ester profiles — a ginjo yeast produces bright fruity esters even at the same SMV as a sake fermented with a more neutral strain. Water mineral content, rice variety, and polishing ratio all shape the final flavor landscape. Evaluating sake through SMV and san-do together is far more predictive than either measurement alone, and experienced tasters still rely primarily on sensory assessment over label numbers.
What SMV and acidity should I look for when pairing with food?
For delicate dishes — white fish, tofu, lightly seasoned vegetable preparations — seek Ginjo or Junmai Ginjo with SMV +3 to +5 and san-do around 1.2–1.4. The low acid and moderate dryness avoid overwhelming subtle flavors. For richer dishes — grilled meats, aged cheeses, miso-based preparations — look for Junmai or Kimoto styles with SMV -1 to +3 and san-do 1.6–2.0; the higher acidity cuts through fat and the fuller body stands up to bold flavors. For dessert pairings, very sweet sake (SMV -5 or below) with moderate acid works well with fruit-based sweets, mirroring the pairing logic of Sauternes with foie gras — matching richness while using acidity to provide contrast.