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var kaptcha = require("kaptcha")

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kaptcha v1.0.4

simple 6 digit captcha image middleware for express, modified from captcha middleware.


simple 6 digit captcha image middleware for express, modified from captcha middleware


Canvas is required, please follow canvas instruction to install canvase dependencies. Canvas Wiki

Once canvas is installed successfully, run npm command to install kaptcha.

npm install kaptcha


As middleware (express-session middleware is required):

var kaptcha = require('kaptcha');

app.get('/kaptcha.png', kaptcha({ 
  color: 'rgb(0, 0, 0)', 
  background: 'rgb(255, 255, 255)',
  width: 100, 
  height: 30 
}))'/authenticate', function(req, res) {
  console.log(req.session.captcha == req.body.captcha);


var kaptcha = require('kaptcha');

app.get('/captcha', function(req, res) {
  var code = kaptcha.generateCode();
  kaptcha.generateImage(req, res, { width: 100, height: 30, text: code });



font color


background color


image width


image height


Optional captcha random code for generateImage(), and will be ignored in kaptcha middleware function.

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