Refer to wiki for specific item base rates (usually 1% – 5%).
Combined value of Stats + Humanity + Gear (e.g., Gold Serpent Ring).
Farming Analysis
Adjusted Drop Rate (Per Kill):0%
Probability of ≥1 Drop:0%
Avg. Kills for One Drop:0
Farming Difficulty:–
*This calculation uses the standard multiplier formula: Base Rate × (Item Discovery / 100). "Probability of ≥1 Drop" represents the chance you will get the item at least once within the entered number of attempts based on cumulative binomial probability.
Optimizing Your Farming Run in Dark Souls
Whether you are hunting for the Balder Side Sword, a Black Knight weapon, or Covenant items like Sunlight Medals, understanding how RNG (Random Number Generation) works is vital to preserving your sanity. This calculator helps you estimate your success chances based on your character's current stats and equipment.
Understanding Item Discovery
Item Discovery is the governing statistic for loot drops in the Souls series. While the exact formulas can vary slightly between titles (DS1, DS2, DS3, and Elden Ring), the core concept remains consistent: it acts as a multiplier to the base drop rate of an item.
Base Drop Rate: Every enemy has a specific loot table. Rare items often have base drop rates as low as 1% or 2%.
Item Discovery 100: This is the standard baseline for most characters. It represents a 1.0x multiplier.
Item Discovery 410 (DS1 Cap): Achieved with 10 soft humanity and the Symbol of Avarice or Covetous Gold Serpent Ring. This boosts drop rates significantly (approx. 4.1x).
The Mathematics of Farming
Many players fall into the "Gambler's Fallacy," believing that if an item has a 1% drop rate, they are guaranteed to get it after 100 kills. Mathematically, this is incorrect.
We use the formula P = 1 - (1 - drop_rate)^n, where n is the number of kills. Even with a 1% drop rate, after 100 kills, there is still roughly a 36% chance you will not have found the item yet. This calculator determines the cumulative probability, giving you a realistic expectation of how long a farming session might take.
Tips for Maximizing Drop Rates
To reduce the "Avg. Kills for One Drop," consider these adjustments:
Equip the Covetous Gold Serpent Ring: This is the most efficient way to boost discovery without stat investment.
Use Rusted Coins: In games like DS3 and Elden Ring, these consumables provide a temporary boost to Item Discovery.
Increase Luck (or Arcane): In DS3 and Elden Ring, specific stats scale your innate Item Discovery.
Symbol of Avarice: The mimic headgear boosts discovery but drains HP. Use with caution.
Use the calculator above to see how increasing your Item Discovery from 100 to 410 drastically changes the expected number of attempts required to obtain rare covenant items.
function calculateSoulsDrop() {
// 1. Get input values
var baseRateInput = document.getElementById('baseDropRate').value;
var discoveryInput = document.getElementById('itemDiscovery').value;
var killsInput = document.getElementById('killCount').value;
// 2. Validate inputs
if (baseRateInput === "" || discoveryInput === "" || killsInput === "") {
alert("Please fill in all fields (Base Rate, Item Discovery, and Kills).");
return;
}
var baseRate = parseFloat(baseRateInput);
var discovery = parseFloat(discoveryInput);
var kills = parseInt(killsInput);
if (baseRate < 0 || discovery < 0 || kills 1) {
adjustedRateDecimal = 1;
}
// Binomial Probability: Chance of getting at least 1 drop in N trials
// P(Success >= 1) = 1 – P(Fail)^N
var probFailSingle = 1 – adjustedRateDecimal;
var probFailCumulative = Math.pow(probFailSingle, kills);
var probSuccessCumulative = 1 – probFailCumulative;
// Average kills required = 1 / Probability per kill
var avgKills = 0;
if (adjustedRateDecimal > 0) {
avgKills = 1 / adjustedRateDecimal;
} else {
avgKills = Infinity;
}
// 4. Determine Difficulty Tier
var difficultyText = "";
var difficultyColor = "#fff";
// Use the cumulative success chance to gauge difficulty for this specific run
if (probSuccessCumulative >= 0.9) {
difficultyText = "Very Likely";
difficultyColor = "#4caf50"; // Green
} else if (probSuccessCumulative >= 0.5) {
difficultyText = "Probable";
difficultyColor = "#d4af37"; // Gold
} else if (probSuccessCumulative >= 0.2) {
difficultyText = "Unlikely";
difficultyColor = "#ff9800"; // Orange
} else {
difficultyText = "Pray to RNGesus";
difficultyColor = "#f44336"; // Red
}
// 5. Display Results
document.getElementById('resAdjustedRate').innerText = (adjustedRateDecimal * 100).toFixed(2) + "%";
document.getElementById('resProbability').innerText = (probSuccessCumulative * 100).toFixed(2) + "%";
if (avgKills === Infinity) {
document.getElementById('resAvgKills').innerText = "Infinite";
} else {
document.getElementById('resAvgKills').innerText = Math.ceil(avgKills);
}
var diffEl = document.getElementById('resDifficulty');
diffEl.innerText = difficultyText;
diffEl.style.color = difficultyColor;
// Show result div
document.getElementById('calcResult').style.display = "block";
}