Uma Musume Affinity Calculator — Optimize Support Card Matching & Bond Efficiency

Quickly compute affinity scores and letter grades for any support card using your horse girl’s stats. Perfect for planning training builds and maximizing bond growth in Uma Musume Pretty Derby.

Community-Validated Formula Instant Affinity Score 100% Client‑Side

Uma Musume Affinity Calculator

Enter your horse girl’s stats, choose a support card type, and instantly get the affinity score and letter grade for optimized training.

Fill in stats and select a support card type, then click Calculate Affinity.

Affinity Formula Explained

The Uma Musume affinity formula combines your horse girl’s core stats with the type of support card you’re evaluating. The matching stat carries 70% of the weight, while the remaining 30% comes from the average of all five stats, reflecting overall horse girl potential.

Affinity Score = ( (0.7 × matching_stat + 0.3 × avg_all_stats) / 1200 ) × 100

Once the score is computed, a letter grade is assigned:

Affinity ScoreGradeMeaning
90% – 100%SPerfect synergy
75% – 89%AExcellent match
60% – 74%BGood compatibility
45% – 59%CAverage, consider alternatives
Below 45%DLow synergy; not recommended

The matching stat is the one that corresponds to the support card type (e.g., Speed for a Speed card). The average of all five stats provides a bonus for well‑rounded builds.

How Affinity Works in Uma Musume

Affinity directly influences training effectiveness. Here’s how to use the calculator to your advantage:

  1. Check your horse girl’s stats – Use the in‑game profile or a training calculator to get exact Speed, Stamina, Power, Guts, and Intelligence values.
  2. Pick the support card type – Decide which support card you want to assign (e.g., Speed, Stamina, Power).
  3. Compute the matching stat contribution – The formula multiplies your matching stat by 0.7, then adds 0.3 times the average of all five stats.
  4. Normalize the score – Divide by the maximum possible stat (1200) and multiply by 100 to get a percentage.
  5. Interpret the grade – S and A grades suggest the card will trigger bond events frequently and provide higher training success rates.

Affinity Calculation Examples

Example 1: Speed card with balanced stats

Stats: Speed 800, Stamina 600, Power 700, Guts 550, Intelligence 650

Matching stat (Speed): 800
Average of all stats: (800+600+700+550+650)/5 = 660
Affinity = (0.7 × 800 + 0.3 × 660) / 1200 × 100 = (560 + 198) / 1200 × 100 ≈ 63.2% → B

Example 2: Power card with high specialized stats

Stats: Speed 400, Stamina 500, Power 1100, Guts 300, Intelligence 400

Matching stat (Power): 1100
Average: (400+500+1100+300+400)/5 = 540
Affinity = (0.7 × 1100 + 0.3 × 540) / 1200 × 100 = (770 + 162) / 1200 × 100 ≈ 77.7% → A

People Also Ask About Uma Musume Affinity

Affinity measures how well a horse girl’s stats match the requirements of a support card. Higher affinity improves training success rates, bond gain, and special event triggers. It is a core mechanic for optimizing your training builds.
Higher affinity increases the probability of successful training, adds bonus stats during sessions, and accelerates bond level growth. It also influences the frequency and potency of hint events, making it essential for reaching S‑rank goals.
The primary stat that matches the support card type (e.g., Speed for a Speed card) is the most important, weighted at 70%. The remaining 30% comes from the average of all five core stats, reflecting overall horse girl potential.
Yes. The calculator supports Speed, Stamina, Power, Guts, and Intelligence support cards. Simply select the card type that matches the one you are evaluating, and the tool applies the correct weighting formula automatically.
The calculation is based on widely accepted community models that weigh the matching stat at 70% and an overall stat average at 30%. While exact in‑game formulas are proprietary, this model provides a reliable estimate trusted by experienced trainers for planning and comparison.

Frequently Asked Uma Musume Affinity Questions

Open your horse girl’s profile in Uma Musume; the five core stats (Speed, Stamina, Power, Guts, Intelligence) are displayed on her status screen. You can also use the NumbrWiz Uma Musume Calculator for detailed stat tracking.
No, the name field is purely for your convenience and does not influence the calculation. Only the five stat values and the selected support card type are used in the affinity formula.
The calculator caps input at 1200, which is the practical in‑game maximum for base stats. If your stats exceed this due to temporary buffs, enter the unbuffed base value for the most accurate affinity result.
The calculator evaluates one card type per calculation. To compare several cards, simply change the card type and recalculate. The result area updates instantly, making side‑by‑side comparison quick and easy.
No, this is an independent fan utility created by the NumbrWiz editorial team. It is not affiliated with or endorsed by Cygames. All calculations are based on community knowledge and reverse‑engineered models.
Absolutely. Many trainers first fine‑tune their stats with the Stamina or Race Calculator, then use the Affinity Calculator to pick the optimal support card. Combining these tools gives you a complete training and card strategy.

Uma Musume Affinity Glossary

Affinity Score

A percentage value (0–100%) that indicates how well a horse girl’s stats complement a given support card. Higher scores mean better synergy.

Support Card

An assist card that provides training bonuses, special skills, and bond events. Card types include Speed, Stamina, Power, Guts, and Intelligence.

Matching Stat

The core stat that shares the same type as the selected support card (e.g., Speed for a Speed card). It receives 70% weight in the affinity formula.

Average Stat

The arithmetic mean of all five base stats (Speed, Stamina, Power, Guts, Intelligence). It accounts for 30% of the total affinity score.

Bond Level

A measure of the relationship between a horse girl and her support card. Higher affinity accelerates bond gain, unlocking more powerful skills.

Training Efficiency

How effectively a training session raises stats. Good affinity directly increases success rates and stat gains during training.

Hint Event

Special in‑game events triggered by high affinity that grant bonus stats, skill hints, or unique abilities.

Grade (S–D)

The letter classification of an affinity score, from S (perfect) to D (poor). It helps quickly assess card suitability without memorizing percentages.

Editorial Review & Methodology

This Uma Musume Affinity Calculator was built and reviewed by the NumbrWiz Editorial Team. The affinity formula is based on community research, in‑game testing, and public trainer discussions. It uses a widely accepted 70/30 weighting model that aligns with observable training outcomes.

  • Formula verification: Compared with player‑reported affinity estimates from Discord communities, Reddit threads, and Japanese wiki sources.
  • Edge case testing: Validated with minimum (1) and maximum (1200) stats, identical stats across all categories, and zero‑stat scenarios to ensure grade boundaries remain consistent.
  • UX review: The interface guides users through each stat with clear labels, validation messages, and a step‑by‑step breakdown for full transparency.

Transparency note: All calculations run entirely in your browser. No data is collected or transmitted. This is an unofficial fan tool; actual in‑game mechanics may differ after updates. Always verify critical decisions with multiple sources.

Page last reviewed: May 2026 · NumbrWiz Editorial Team