EC2 Instance Types Basics – AWS Certified Cloud Practitioner

🧠 EC2 Instance Types

Think of EC2 instances as different machines built for different jobs. Not every workload needs the same thing — some want balanced performance, some want raw CPU, some need huge memory, others need fast storage. AWS gives you a family of instance types, each tuned for one of those.

🏷️ Reading an instance name

<div class="infographic-ec2name">
<style>
.infographic-ec2name {
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  --ink-soft:#5c5c5c;
  --paper:#ffffff;
  --paper-alt:#f6f4ef;
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  --display-font:Georgia,'Iowan Old Style',serif;
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  padding:2rem 1.25rem;
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  margin:0 auto;
  border-radius:14px;
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}
.infographic-ec2name[data-theme="dark"]{
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.infographic-ec2name *{box-sizing:border-box}
.en-name{text-align:center;font-family:var(--mono-font);font-weight:800;font-size:2.1rem;letter-spacing:.01em;margin-bottom:.5rem}
.en-name .seg{transition:color .15s;cursor:default}
.en-name .seg.is-active{color:var(--accent)}
.en-parts{display:flex;justify-content:center;gap:.6rem;margin-bottom:1.75rem;flex-wrap:wrap;padding-bottom:1.5rem;border-bottom:1px solid var(--line)}
.en-part{border:1.5px solid var(--line);border-radius:999px;padding:.45rem 1rem;font-weight:700;font-family:var(--mono-font);font-size:.95rem;cursor:pointer;background:var(--paper-alt);transition:border-color .15s,background .15s}
.en-part:hover{border-color:var(--accent)}
.en-part.is-active{border-color:var(--accent);background:var(--accent-soft);color:var(--accent)}
.en-breakdown{display:grid;grid-template-columns:repeat(3,1fr);gap:1.2rem;margin-bottom:0}
@media (max-width:560px){.en-breakdown{grid-template-columns:1fr}}
.en-item{text-align:center;padding:.8rem .5rem;border-radius:10px;transition:background .15s}
.en-item.is-active{background:var(--accent-soft)}
.en-item .icon{font-size:2rem;margin-bottom:.4rem}
.en-item .name{font-weight:700;font-size:.88rem}
.en-item .detail{font-size:.78rem;color:var(--ink-soft);margin-top:.2rem}
@media (prefers-reduced-motion:reduce){
.infographic-ec2name *{transition-duration:.001ms!important}
}
</style>

<div class="en-name" id="en-name">
<span class="seg" data-seg="class">m</span><span class="seg" data-seg="gen">5</span><span>.</span><span class="seg" data-seg="size">2xlarge</span>
</div>

<div class="en-parts">
<div class="en-part is-active" data-p="class">m</div>
<div class="en-part" data-p="gen">5</div>
<div class="en-part" data-p="size">2xlarge</div>
</div>

<div class="en-breakdown">
<div class="en-item" data-b="class">
<div class="icon">🧠</div>
<div class="name">Instance Class</div>
<div class="detail" id="en-class-detail">M = General Purpose</div>
</div>

<div class="en-item" data-b="gen">
<div class="icon">⏱️</div>
<div class="name">Generation</div>
<div class="detail" id="en-gen-detail">5 = 5th generation</div>
</div>

<div class="en-item" data-b="size">
<div class="icon">📶</div>
<div class="name">Size</div>
<div class="detail" id="en-size-detail">2xlarge = relative size (bigger = more vCPU + RAM)</div>
</div>
</div>

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</div>

.demo {
  font-family: system-ui, sans-serif;
  padding: 16px;
}

.demo h1 {
  color: #2563eb;
  margin: 0 0 8px;
}

.demo p {
  color: #4b5563;
  margin: 0;
}

document.querySelector('.demo h1')?.addEventListener('click', () => {
  alert('Hello from live preview!');
});

Take m5.2xlarge:

m → instance class (General Purpose)
5 → generation (higher = newer hardware)
2xlarge → size (bigger = more CPU + RAM, and more cost)

Simple rule: bigger size = more power = higher price.

⚡ Main EC2 Instance Types

<div class="infographic-ec2name">
<style>
.infographic-ec2name {
  --ink:        #1a1a1a;
  --ink-soft:   #5c5c5c;
  --paper:      #ffffff;
  --paper-alt:  #f6f4ef;
  --accent:     #2563eb;
  --accent-soft:#e3ebfd;
  --line:       #ddd6c9;
  --ok:         #1e8e5a;
  --ok-soft:    #e2f6ec;
  --bad:        #c0392b;
  --bad-soft:   #fbe9e7;
  --display-font: Georgia, 'Iowan Old Style', serif;
  --mono-font: 'SF Mono', Menlo, Consolas, monospace;

  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--ink);
  background: var(--paper);
  padding: 2rem 1.25rem 2.5rem;
  max-width: 720px;
  margin: 0 auto;
  border-radius: 14px;
  box-sizing: border-box;
}
.infographic-ec2name[data-theme="dark"] {
  --ink:        #e8e6e1;
  --ink-soft:   #9a968c;
  --paper:      #121212;
  --paper-alt:  #1e1e26;
  --accent:     #6f9bff;
  --accent-soft:#1c2740;
  --line:       #2c313d;
  --ok:         #4fbf87;
  --ok-soft:    #143024;
  --bad:        #e57373;
  --bad-soft:   #3a2222;
}
.infographic-ec2name * { box-sizing: border-box; }

.en-name { text-align: center; font-family: var(--mono-font); font-weight: 800; font-size: 2.1rem;
  letter-spacing: 0.01em; margin-bottom: 0.5rem; }
.en-name .seg { transition: color 0.15s; }

.en-parts { display: flex; justify-content: center; gap: 0.6rem; margin-bottom: 1.75rem; flex-wrap: wrap;
  padding-bottom: 1.5rem; border-bottom: 1px solid var(--line); }
.en-part { border: 1.5px solid var(--line); border-radius: 999px; padding: 0.45rem 1rem; font-weight: 700;
  font-family: var(--mono-font); font-size: 0.95rem; cursor: pointer; background: var(--paper-alt);
  transition: border-color 0.15s, background 0.15s, color 0.15s; }
.en-part:hover { border-color: var(--accent); }
.en-part.is-active { border-color: var(--accent); background: var(--accent-soft); color: var(--accent); }

.en-breakdown { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.2rem; margin-bottom: 2rem; }
@media (max-width: 560px) { .en-breakdown { grid-template-columns: 1fr; } }
.en-item { text-align: center; padding: 0.8rem 0.5rem; border-radius: 10px; cursor: pointer; transition: background 0.15s; }
.en-item.is-active { background: var(--accent-soft); }
.en-item .icon { font-size: 2rem; margin-bottom: 0.4rem; }
.en-item .name { font-weight: 700; font-size: 0.88rem; }
.en-item .detail { font-size: 0.78rem; color: var(--ink-soft); margin-top: 0.2rem; }

.en-builder { border: 1.5px solid var(--line); border-radius: 12px; padding: 1.2rem 1.3rem; background: var(--paper-alt);
  margin-bottom: 1.75rem; }
.en-builder-title { font-weight: 700; font-size: 0.9rem; margin: 0 0 0.9rem; text-align: center; }
.en-builder-row { display: flex; justify-content: center; gap: 0.6rem; flex-wrap: wrap; }
.en-builder-row select { font: inherit; font-size: 0.85rem; padding: 0.4rem 0.6rem; border-radius: 6px;
  border: 1px solid var(--line); background: var(--paper); color: var(--ink); }

/* --- Good fit / bad fit task demo --- */
.en-task { border: 1.5px solid var(--line); border-radius: 12px; padding: 1.2rem 1.3rem; background: var(--paper-alt); }
.en-task-title { font-weight: 700; font-size: 0.9rem; margin: 0 0 0.9rem; text-align: center; }
.en-task-btns { display: flex; justify-content: center; gap: 0.6rem; flex-wrap: wrap; margin-bottom: 1.1rem; }
.en-task-btns button { font: inherit; font-size: 0.82rem; font-weight: 700; padding: 0.5rem 0.95rem;
  border-radius: 999px; cursor: pointer; border: 1.5px solid var(--line); background: var(--paper); color: var(--ink); }
.en-task-btns button.good { border-color: var(--ok); color: var(--ok); }
.en-task-btns button.bad { border-color: var(--bad); color: var(--bad); }
.en-task-btns button:disabled { opacity: 0.5; cursor: default; }

.en-task-label { text-align: center; font-size: 0.85rem; font-weight: 600; margin-bottom: 0.6rem; min-height: 1.2em; }
.en-progress-track { height: 12px; border-radius: 999px; background: var(--line); overflow: hidden; margin-bottom: 0.6rem; }
.en-progress-fill { height: 100%; width: 0%; background: var(--ink-soft); border-radius: 999px; }
.en-progress-fill.good { background: var(--ok); transition: width 0.9s linear; }
.en-progress-fill.bad { background: var(--bad); animation: en-struggle 3.2s steps(18) forwards; }
@keyframes en-struggle {
  0%   { width: 0%; }
  15%  { width: 18%; }
  22%  { width: 19%; }
  40%  { width: 45%; }
  46%  { width: 44%; }
  70%  { width: 68%; }
  76%  { width: 66%; }
  100% { width: 100%; }
}
.en-task-result { text-align: center; font-size: 0.85rem; min-height: 1.3em; font-weight: 600; }
.en-task-result.ok { color: var(--ok); }
.en-task-result.bad { color: var(--bad); }

@media (prefers-reduced-motion: reduce) {
  .infographic-ec2name * { transition-duration: 0.001ms !important; animation: none !important; }
}
</style>

<div class="en-name" id="en-name"></div>

<div class="en-parts">
  <div class="en-part" data-p="class"></div>
  <div class="en-part" data-p="gen"></div>
  <div class="en-part" data-p="size"></div>
</div>

<div class="en-breakdown">
  <div class="en-item" data-b="class">
    <div class="icon">🧠</div>
    <div class="name">Instance Class</div>
    <div class="detail" id="en-class-detail"></div>
  </div>
  <div class="en-item" data-b="gen">
    <div class="icon">⏱️</div>
    <div class="name">Generation</div>
    <div class="detail" id="en-gen-detail"></div>
  </div>
  <div class="en-item" data-b="size">
    <div class="icon">📶</div>
    <div class="name">Size</div>
    <div class="detail" id="en-size-detail"></div>
  </div>
</div>

<div class="en-builder">
  <p class="en-builder-title">Build your own instance name</p>
  <div class="en-builder-row">
    <select id="en-sel-class">
      <option value="m" selected>m — General Purpose</option>
      <option value="c">c — Compute Optimized</option>
      <option value="r">r — Memory Optimized</option>
      <option value="i">i — Storage Optimized</option>
    </select>
    <select id="en-sel-gen">
      <option>5</option>
      <option selected>6</option>
      <option>7</option>
    </select>
    <select id="en-sel-size">
      <option>micro</option>
      <option>small</option>
      <option>large</option>
      <option selected>xlarge</option>
      <option>2xlarge</option>
      <option>4xlarge</option>
    </select>
  </div>
</div>

<div class="en-task">
  <p class="en-task-title">See what this instance is actually good at</p>
  <div class="en-task-btns">
    <button class="good" id="en-btn-good">✅ Try a good-fit task</button>
    <button class="bad" id="en-btn-bad">❌ Try a mismatched task</button>
  </div>
  <div class="en-task-label" id="en-task-label">Pick a task above.</div>
  <div class="en-progress-track"><div class="en-progress-fill" id="en-progress-fill"></div></div>
  <div class="en-task-result" id="en-task-result">&nbsp;</div>
</div>

<script>
(function () {
  const wrapper = document.currentScript.closest('.infographic-ec2name')
    || document.querySelector('.infographic-ec2name');
  const bodyAttr = document.body.getAttribute('data-darkmode');
  let dark;
  if (bodyAttr === 'true') { dark = true; }
  else if (bodyAttr === 'false') { dark = false; }
  else {
    const match = document.cookie.match(/(?:^|;\s*)darkMode=([^;]+)/);
    dark = match ? match[1] === 'true' : false;
  }
  if (dark) wrapper.setAttribute('data-theme', 'dark');

  const classNames = { m: 'General Purpose', c: 'Compute Optimized', r: 'Memory Optimized', i: 'Storage Optimized' };
  const taskData = {
    m: { good: 'Serving a web page', bad: 'Training a large ML model' },
    c: { good: 'Encoding a batch of video', bad: 'Hosting a huge in-memory cache' },
    r: { good: 'Querying an in-memory database', bad: 'Heavy video encoding' },
    i: { good: 'High-speed data read/write', bad: 'Large-scale ML training' }
  };

  const nameEl = wrapper.querySelector('#en-name');
  const selClass = wrapper.querySelector('#en-sel-class');
  const selGen = wrapper.querySelector('#en-sel-gen');
  const selSize = wrapper.querySelector('#en-sel-size');
  const classDetail = wrapper.querySelector('#en-class-detail');
  const genDetail = wrapper.querySelector('#en-gen-detail');
  const sizeDetail = wrapper.querySelector('#en-size-detail');
  const chipClass = wrapper.querySelector('.en-part[data-p="class"]');
  const chipGen = wrapper.querySelector('.en-part[data-p="gen"]');
  const chipSize = wrapper.querySelector('.en-part[data-p="size"]');

  function render() {
    const c = selClass.value;
    const g = selGen.value;
    const s = selSize.value;

    nameEl.innerHTML =
      '<span class="seg" data-seg="class">' + c + '</span>' +
      '<span class="seg" data-seg="gen">' + g + '</span>' +
      '<span>.</span>' +
      '<span class="seg" data-seg="size">' + s + '</span>';

    chipClass.textContent = c;
    chipGen.textContent = g;
    chipSize.textContent = s;

    classDetail.textContent = c.toUpperCase() + ' = ' + classNames[c];
    genDetail.textContent = g + ' = generation ' + g;
    sizeDetail.textContent = s + ' = relative size (bigger = more vCPU + RAM)';

    resetTask();
  }

  function setActive(key) {
    wrapper.querySelectorAll('.en-part').forEach(p => p.classList.toggle('is-active', p.dataset.p === key));
    wrapper.querySelectorAll('.en-item').forEach(b => b.classList.toggle('is-active', b.dataset.b === key));
  }
  wrapper.querySelectorAll('.en-part').forEach(p => p.addEventListener('click', () => setActive(p.dataset.p)));
  wrapper.querySelectorAll('.en-item').forEach(b => b.addEventListener('click', () => setActive(b.dataset.b)));

  [selClass, selGen, selSize].forEach(el => el.addEventListener('change', render));

  // --- Good-fit / mismatched task demo ---
  const btnGood = wrapper.querySelector('#en-btn-good');
  const btnBad = wrapper.querySelector('#en-btn-bad');
  const taskLabel = wrapper.querySelector('#en-task-label');
  const progressTrack = wrapper.querySelector('.en-progress-track');
  const taskResult = wrapper.querySelector('#en-task-result');
  let running = false;

  function resetTask() {
    running = false;
    btnGood.disabled = false;
    btnBad.disabled = false;
    taskLabel.textContent = 'Pick a task above.';
    taskResult.textContent = '\u00a0';
    taskResult.className = 'en-task-result';
    progressTrack.innerHTML = '<div class="en-progress-fill" id="en-progress-fill"></div>';
  }

  function runTask(kind) {
    if (running) return;
    running = true;
    btnGood.disabled = true;
    btnBad.disabled = true;

    const c = selClass.value;
    const task = taskData[c][kind];
    taskLabel.textContent = task;
    taskResult.textContent = '\u00a0';
    taskResult.className = 'en-task-result';

    progressTrack.innerHTML = '<div class="en-progress-fill ' + kind + '" id="en-progress-fill"></div>';
    const fill = wrapper.querySelector('#en-progress-fill');

    if (kind === 'good') {
      requestAnimationFrame(() => { fill.style.width = '100%'; });
      setTimeout(() => {
        taskResult.textContent = '✅ Done fast — this is exactly what this instance is built for.';
        taskResult.classList.add('ok');
        running = false;
        btnGood.disabled = false;
        btnBad.disabled = false;
      }, 950);
    } else {
      setTimeout(() => {
        taskResult.textContent = '⚠️ Finally done — took a lot longer and strained the instance.';
        taskResult.classList.add('bad');
        running = false;
        btnGood.disabled = false;
        btnBad.disabled = false;
      }, 3300);
    }
  }

  btnGood.addEventListener('click', () => runTask('good'));
  btnBad.addEventListener('click', () => runTask('bad'));

  render();
})();
</script>
</div>

.demo {
  font-family: system-ui, sans-serif;
  padding: 16px;
}

.demo h1 {
  color: #2563eb;
  margin: 0 0 8px;
}

.demo p {
  color: #4b5563;
  margin: 0;
}

document.querySelector('.demo h1')?.addEventListener('click', () => {
  alert('Hello from live preview!');
});

⚖️ General Purpose

The balanced option Good for web servers, small databases, backend apps. Even split of CPU, memory, and networking.
👉 Example: t3.micro (FREE tier — you’ll use this a lot)

🧮 Compute Optimized

CPU-heavy Good for batch jobs, video encoding, ML, anything computation-heavy. Named C5, C6, etc.

🧠 Memory Optimized

RAM-heavy Good for large databases, real-time analytics, caching (Redis and friends) — anything holding huge datasets in memory. Named R5, X1, Z1.

💾 Storage Optimized

Built for fast disk I/O Good for big data, data warehousing, high-throughput databases. Named I, D, H1.

Quick comparison

Type	vCPU	Memory	Strength	Best for
t3.micro	2	1 GB	Balanced	Small apps, free tier
c6i.xlarge	4	8 GB	CPU	Compute-heavy tasks
r6i.xlarge	4	32 GB	Memory	Databases, caching
i4i.large	2	16 GB	Storage	Fast data processing

🌐 One useful tool

ec2instances.info — compare every instance type side by side, check pricing, and filter by CPU or memory.

The one thing to remember

General → balanced
Compute → CPU power
Memory → RAM heavy
Storage → fast data access