Email validation reference
Arcjet allows you validate & verify an email address. This is useful for preventing users from signing up with fake email addresses and can significantly reduce the amount of spam or fraudulent accounts.
Configuration
Email validation is configured by specifying the email types you wish to block and whether you wish to modify certain validation options.
The configuration definition is:
type EmailOptions = { mode?: "LIVE" | "DRY_RUN"; block?: ArcjetEmailType[]; requireTopLevelDomain?: boolean; // default: true allowDomainLiteral?: boolean; // default: false};The arcjet client is configured with one or many validateEmail rules which
take EmailOptions.
Which email types to block is configured by listing the types in the configuration block.
The validation options can usually be left as the defaults. However, if you wish to allow certain types of email addresses, you can modify the options:
requireTopLevelDomain: Whether or not to allow email addresses that don’t contain at least 2 domain segments (the domain name and TLD). Defaults totrue. Changing tofalsemeans thatfoo@barwould be allowed.allowDomainLiteral: Whether or not to allow email addresses with domain literals. Defaults tofalse. Changing totruemeans thatfoo@[123.456.789.0]would be allowed.
Decision
Arcjet provides a single protect function that is used to execute your
protection rules. This requires a request argument which is the request
context as passed to the request handler. When configured with a validateEmail
rule it also requires an additional email prop.
This function returns a Promise that resolves to an
ArcjetDecision object. This contains the following properties:
id(string) - The unique ID for the request. This can be used to look up the request in the Arcjet dashboard. It is prefixed withreq_for decisions involving the Arcjet cloud API. For decisions taken locally, the prefix islreq_.conclusion(ArcjetConclusion) - The final conclusion based on evaluating each of the configured rules. If you wish to accept Arcjet’s recommended action based on the configured rules then you can use this property.reason(ArcjetReason) - An object containing more detailed information about the conclusion.results(ArcjetRuleResult[]) - An array ofArcjetRuleResultobjects containing the results of each rule that was executed.ip(ArcjetIpDetails) - An object containing Arcjet’s analysis of the client IP address. See the SDK reference for more information.
You check if a deny conclusion has been returned by an email validation rule by
using decision.isDenied() and decision.reason.isEmail().
You can iterate through the results and check whether an email validation rule was applied:
for (const result of decision.results) { console.log("Rule Result", result);}This example will log the full result as well as the email validation rule:
import arcjet, { detectBot, validateEmail } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return new Response("Forbidden", { status: 403 }); }
return new Response("Hello world"); }),};import arcjet, { detectBot, validateEmail } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return new Response("Forbidden", { status: 403 }); }
return new Response("Hello world"); }),};import arcjet, { validateEmail, detectBot } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function POST(req: Request) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return NextResponse.json({ error: "Forbidden" }, { status: 403 }); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { validateEmail, detectBot } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function POST(req) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return NextResponse.json({ error: "Forbidden" }, { status: 403 }); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { detectBot, validateEmail } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default async function handler(req, res) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { detectBot, validateEmail } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); }
res.status(200).json({ name: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { detectBot, validateEmail } from "@arcjet/sveltekit";import { error, json, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function POST(event: RequestEvent) { const decision = await aj.protect(event, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return error(403, "Forbidden"); }
return json({ message: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { detectBot, validateEmail } from "@arcjet/sveltekit";import { error, json } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function POST(event) { const decision = await aj.protect(event, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); } }
if (decision.isDenied()) { return error(403, "Forbidden"); }
return json({ message: "Hello world" });}import arcjet, { detectBot, validateEmail } from "@arcjet/node";import express from "express";
const app = express();const port = 3000;
app.use(express.urlencoded({ extended: false }));
const aj = arcjet({ // Get your site key from https://app.arcjet.com and set it as an environment // variable rather than hard coding. key: process.env.ARCJET_KEY!, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
app.post("/", async (req, res) => { //const email = req.body.email; const email = "test@0zc7eznv3rsiswlohu.tk"; // Disposable email for demo console.log("Email received: ", email);
const decision = await aj.protect(req, { email }); console.log("Arcjet decision", decision);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { res.writeHead(403, { "Content-Type": "application/json" }); res.end(JSON.stringify({ error: "Forbidden" })); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello World", email })); }});
app.listen(port, () => { console.log(`Example app listening on port ${port}`);});import arcjet, { detectBot, validateEmail } from "@arcjet/node";import express from "express";
const app = express();const port = 3000;
app.use(express.urlencoded({ extended: false }));
const aj = arcjet({ // Get your site key from https://app.arcjet.com and set it as an environment // variable rather than hard coding. key: process.env.ARCJET_KEY, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
app.post("/", async (req, res) => { //const email = req.body.email; const email = "test@0zc7eznv3rsiswlohu.tk"; // Disposable email for demo console.log("Email received: ", email);
const decision = await aj.protect(req, { email }); console.log("Arcjet decision", decision);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isEmail()) { console.log("Email rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { res.writeHead(403, { "Content-Type": "application/json" }); res.end(JSON.stringify({ error: "Forbidden" })); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello World", email })); }});
app.listen(port, () => { console.log(`Example app listening on port ${port}`);});Checking the email type
Arcjet will return the type of email address that was verified. This will be one or several of the reported email types.
// See https://docs.arcjet.com/email-validation/concepts#email-typestype ArcjetEmailType = | "DISPOSABLE" // Disposable email address from a throwaway email service | "FREE" // Email address from a free email service | "NO_MX_RECORDS" // Email address with no MX records i.e. is undeliverable | "NO_GRAVATAR" // Email address with no Gravatar profile | "INVALID"; // Email address that is invalidError handling
Arcjet is designed to fail open so that a service issue or misconfiguration does
not block all requests. The SDK will also time out and fail open after 1000ms
when NODE_ENV or ARCJET_ENV is development and 500ms otherwise. However,
in most cases, the response time will be less than 20-30ms.
If there is an error condition, Arcjet will return an ERROR conclusion.
import arcjet, { validateEmail } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes // return new Response("Service unavailable", { status: 503 }); }
if (decision.isDenied()) { return new Response("Forbidden", { status: 403 }); }
return new Response("Hello world"); }),};import arcjet, { validateEmail } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes // return new Response("Service unavailable", { status: 503 }); }
if (decision.isDenied()) { return new Response("Forbidden", { status: 403 }); }
return new Response("Hello world"); }),};import { env } from "$env/dynamic/private";import arcjet, { validateEmail } from "@arcjet/sveltekit";import { error, json, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export async function POST(event: RequestEvent) { const decision = await aj.protect(event, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return error(503, { message: "Service unavailable" }); }
if (decision.isDenied()) { return error(403, { message: "Forbidden" }); }
return json({ message: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { validateEmail } from "@arcjet/sveltekit";import { error, json } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export async function POST(event) { const decision = await aj.protect(event, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return error(503, { message: "Service unavailable" }); }
if (decision.isDenied()) { return error(403, { message: "Forbidden" }); }
return json({ message: "Hello world" });}import arcjet, { validateEmail } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export default async function handler(req, res) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return res.status(503).json({ error: "Service unavailable" }); }
if (decision.isDenied()) { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { validateEmail } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return res.status(503).json({ error: "Service unavailable" }); }
if (decision.isDenied()) { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { validateEmail } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export async function POST(req: Request) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. // TypeScript will guide you based on the configured rules email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return NextResponse.json({ error: "Service unavailable" }, { status: 503 }); }
if (decision.isDenied()) { return NextResponse.json( { error: "Forbidden", }, { status: 403, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { validateEmail } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, rules: [ validateEmail({ mode: "LIVE", block: ["DISPOSABLE"], }), ],});
export async function POST(req) { const decision = await aj.protect(req, { // The email prop is required when a validateEmail rule is configured. email: "test@0zc7eznv3rsiswlohu.tk", });
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return NextResponse.json({ error: "Service unavailable" }, { status: 503 }); }
if (decision.isDenied()) { return NextResponse.json( { error: "Forbidden", }, { status: 403, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { validateEmail } from "@arcjet/node";import express from "express";
const app = express();const port = 3000;
app.use(express.urlencoded({ extended: false }));
const aj = arcjet({ // Get your site key from https://app.arcjet.com and set it as an environment // variable rather than hard coding. key: process.env.ARCJET_KEY!, rules: [ validateEmail({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only block: ["NO_MX_RECORDS"], // block email addresses with no MX records }), ],});
app.post("/", async (req, res) => { console.log("Email received: ", req.body.email);
const decision = await aj.protect(req, { email: req.body.email, }); console.log("Arcjet decision", decision);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //res.writeHead(503, { "Content-Type": "application/json" }); //res.end(JSON.stringify({ error: "Service unavailable" })); }
if (decision.isDenied()) { res.writeHead(403, { "Content-Type": "application/json" }); res.end(JSON.stringify({ error: "Forbidden" })); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello World", email: req.body.email })); }});
app.listen(port, () => { console.log(`Example app listening on port ${port}`);});import arcjet, { validateEmail } from "@arcjet/node";import express from "express";
const app = express();const port = 3000;
app.use(express.urlencoded({ extended: false }));
const aj = arcjet({ // Get your site key from https://app.arcjet.com and set it as an environment // variable rather than hard coding. key: process.env.ARCJET_KEY, rules: [ validateEmail({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only block: ["NO_MX_RECORDS"], // block email addresses with no MX records }), ],});
app.post("/", async (req, res) => { console.log("Email received: ", req.body.email);
const decision = await aj.protect(req, { email: req.body.email, }); console.log("Arcjet decision", decision);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //res.writeHead(503, { "Content-Type": "application/json" }); //res.end(JSON.stringify({ error: "Service unavailable" })); }
if (decision.isDenied()) { res.writeHead(403, { "Content-Type": "application/json" }); res.end(JSON.stringify({ error: "Forbidden" })); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello World", email: req.body.email })); }});
app.listen(port, () => { console.log(`Example app listening on port ${port}`);});Testing
Arcjet runs the same in any environment, including locally and in CI. You can
use the mode set to DRY_RUN to log the results of rule execution without
blocking any requests.
We have an example test framework you can use to automatically test your rules. Arcjet can also be triggered based using a sample of your traffic.
See the Testing section of the docs for details.