Lambda Provisioned Concurrency Cost Calculator

lambda-provisioned-concurrency-cost-calculator.js

// Global
const secondsPerMonth = 31 * 24 * 3600;

// Lambda (based on: https://aws.amazon.com/lambda/pricing/)
const costPerProvisionedGbs = 0.0000041667;
const costPerMillionRequests = 0.20;
const costPerProvisionedDurationGbs = 0.0000097222;
const costPerDurationGbs = 0.0000166667;

// Warmer
const healthCheckDurationSeconds = 1;
const secondsBetweenWarmerInvocations = 60;

function provisionedConcurrencyCost({
  lambdaMemorySizeMb,
  provisionedConcurrency,
  secondsEnabled
}) {
  const provisionedGb = provisionedConcurrency * (lambdaMemorySizeMb / 1024);
  const provisionedGbs = provisionedGb * secondsEnabled;
  return provisionedGbs * costPerProvisionedGbs;
}

function computeCost({ lambdaMemorySizeMb, millionRequests, duration, provisioned }) {
  const computeSeconds = (millionRequests * 1000000) * duration;
  const computeGbs = computeSeconds * (lambdaMemorySizeMb / 1024);
  return computeGbs * (provisioned ? costPerProvisionedDurationGbs : costPerDurationGbs);
}

function requestCost({ lambdaMemorySizeMb, millionRequests, duration, provisioned }) {
  return (millionRequests * costPerMillionRequests) +
    computeCost({ lambdaMemorySizeMb, millionRequests, duration, provisioned });
}

function manualWarmingCost({ lambdaMemorySizeMb, provisionedConcurrency, secondsEnabled }) {
  const warmingRequestsPerConcurrency = secondsEnabled / secondsBetweenWarmerInvocations;
  const warmingRequests = provisionedConcurrency * warmingRequestsPerConcurrency;
  const millionRequests = warmingRequests / 1000000;

  return requestCost({
    lambdaMemorySizeMb,
    millionRequests,
    duration: healthCheckDurationSeconds,
    provisioned: false
  });
}

function roundCost(cost) {
  return Math.round(cost * 100) / 100;
}

const args = {
  lambdaMemorySizeMb: 256,
  provisionedConcurrency: 100,
  secondsEnabled: secondsPerMonth
};

console.log({
  args,
  provisionedCost: roundCost(provisionedConcurrencyCost(args)),
  warmerCost: roundCost(manualWarmingCost(args))
});