Sequence-to-Sequence Models

Explore Seq2Seq models for translation and text generation.

75 min•By Priygop Team•Last updated: Feb 2026

Applications

Machine Translation
Chatbots
Text Summarization

Simple Seq2Seq with Keras

Example

from tensorflow import keras

encoder_inputs = keras.layers.Input(shape=(None,))
x = keras.layers.Embedding(1000, 64)(encoder_inputs)
encoder_outputs, state_h, state_c = keras.layers.LSTM(64, return_state=True)(x)
encoder_states = [state_h, state_c]

decoder_inputs = keras.layers.Input(shape=(None,))
x = keras.layers.Embedding(1000, 64)(decoder_inputs)
decoder_lstm = keras.layers.LSTM(64, return_sequences=True, return_state=True)
decoder_outputs, _, _ = decoder_lstm(x, initial_state=encoder_states)
decoder_dense = keras.layers.Dense(1000, activation='softmax')
decoder_outputs = decoder_dense(decoder_outputs)

model = keras.models.Model([encoder_inputs, decoder_inputs], decoder_outputs)
model.compile(optimizer='adam', loss='categorical_crossentropy')

Try It Yourself — Natural Language Processing

Try It Yourself — Natural Language ProcessingHTML

HTML Editor

✓ ValidTab = 2 spaces

<!DOCTYPE html>
<html><head><style>
  body { font-family: Arial, sans-serif; padding: 20px; background: #f5f5f5; }
  .container { background: white; padding: 30px; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.1); max-width: 600px; margin: auto; }
  h1 { color: #4A90D9; }
  button { background: #4A90D9; color: white; border: none; padding: 10px 20px; border-radius: 6px; font-weight: bold; cursor: pointer; font-size: 16px; margin: 5px; }
  button:hover { background: #357ABD; }
  .output { background: #1e1e1e; color: #4ec9b0; padding: 15px; border-radius: 8px; margin-top: 15px; font-family: monospace; min-height: 40px; white-space: pre-wrap; }
  input { padding: 8px 12px; border: 2px solid #ddd; border-radius: 6px; font-size: 14px; margin: 5px; }
</style></head><body>
<div class="container">
  <h1>Playground</h1>
  <p>Interactive demo for this module!</p>
  <input id="inp" placeholder="Type something..." />
  <button onclick="runDemo()">Run Demo</button>
  <button onclick="clearOut()">Clear</button>
  <div class="output" id="output">Click Run Demo to start...</div>
</div>
<script>
  var log = [];
  function addLog(m) { log.push(m); document.getElementById('output').textContent = log.join('
'); }
  function clearOut() { log=[]; document.getElementById('output').textContent='Cleared.'; }
  function runDemo() {
    var v = document.getElementById('inp').value || 'example';
    addLog('Processing: ' + v);
    addLog('Reversed: ' + v.split('').reverse().join(''));
    addLog('Length: ' + v.length);
    addLog('---');
  }
</script>
</body></html>

<!DOCTYPE html>
<html><head><style>
  body { font-family: Arial, sans-serif; padding: 20px; background: #f5f5f5; }
  .container { background: white; padding: 30px; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.1); max-width: 600px; margin: auto; }
  h1 { color: #4A90D9; }
  button { background: #4A90D9; color: white; border: none; padding: 10px 20px; border-radius: 6px; font-weight: bold; cursor: pointer; font-size: 16px; margin: 5px; }
  button:hover { background: #357ABD; }
  .output { background: #1e1e1e; color: #4ec9b0; padding: 15px; border-radius: 8px; margin-top: 15px; font-family: monospace; min-height: 40px; white-space: pre-wrap; }
  input { padding: 8px 12px; border: 2px solid #ddd; border-radius: 6px; font-size: 14px; margin: 5px; }
</style></head><body>
<div class="container">
  <h1>Playground</h1>
  <p>Interactive demo for this module!</p>
  <input id="inp" placeholder="Type something..." />
  <button onclick="runDemo()">Run Demo</button>
  <button onclick="clearOut()">Clear</button>
  <div class="output" id="output">Click Run Demo to start...</div>
</div>
<script>
  var log = [];
  function addLog(m) { log.push(m); document.getElementById('output').textContent = log.join('
'); }
  function clearOut() { log=[]; document.getElementById('output').textContent='Cleared.'; }
  function runDemo() {
    var v = document.getElementById('inp').value || 'example';
    addLog('Processing: ' + v);
    addLog('Reversed: ' + v.split('').reverse().join(''));
    addLog('Length: ' + v.length);
    addLog('---');
  }
</script>
</body></html>

Result

Click ▶ Run to see the result

Edit the code on the left, then click Run

HTML|32 lines|1574 chars|✓ Valid syntax

UTF-8

Quick Quiz — Natural Language Processing

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Sequence-to-Sequence Models

Applications

Simple Seq2Seq with Keras

Try It Yourself — Natural Language Processing

Quick Quiz — Natural Language Processing

Additional Resources

Recommended Reading

Online Resources