What is the current widget version?

The current widget version is 2.0. The script src is unversioned so installed embeds always receive the latest patch automatically.

Embed our entire deliverability toolkit on any website.

One <script> tag - nine tools. Reputation, SPF, DKIM, DMARC, blacklist, MX, rDNS, plus searchable bounce-code and glossary references. Let your visitors pick a tool from the dropdown, or pin to just one. Light or dark. Free forever.

Themes

Looks right on every site

Three themes ship by default. Auto follows the visitor's OS preference, no extra config.

support.yoursite.com

Light

Clean, neutral, blends with any light layout.

app.yoursite.com

Dark

Slate palette tuned for dashboards and docs.

Specs

The numbers behind the embed

Lightweight, async, and respectful of your page's performance budget.

Loader weight: <3KB
Install: 1 tag
Themes: 3
Cookies set: 0

3 steps

Copy, paste, publish

No npm install. No webhook setup. No account.

Pick a theme

Open the generator above, choose Light, Dark, or Auto, and set a width.

Paste the snippet

Drop the script tag anywhere in your page HTML — before the closing body tag is ideal.

Publish

The widget appears inline and auto-sizes as visitors open accordion details.

Reference

Customization attributes

Every option is set on the <script> tag — no JS API to learn.

Attribute	Type	Default	Description
`src`	string	required	Always `https://senderreputation.org/assets/js/embed.js`. Unversioned so installed embeds receive the latest patch automatically.
`async`	boolean	recommended	Loads the widget without blocking page render. Strongly recommended on every install.
`data-theme`	string	auto	One of `light`, `dark`, or `auto`. Auto follows the visitor's OS color-scheme preference and live-updates if they switch.
`data-tools`	string	all	Comma-separated allow list of tools to expose in the dropdown menu. Values: `reputation`, `spf`, `dkim`, `dmarc`, `blacklist`, `mx`, `rdns`, `bounce-codes`, `glossary`. Omit or use `all` for the full set. A single value pins the widget to that one tool and hides the menu chevron.
`data-tool`	string	first in list	Which tool opens by default. Must be one of the values from `data-tools`. Visitors can still switch using the dropdown unless you have also pinned with `data-tools`.
`data-domain`	string	empty	Pre-fills the active tool's input with this domain or IP. Useful when the embedding page already knows which domain the visitor cares about - e.g. your own brand domain on a status page, or a customer's domain in a CRM.
`data-autorun`	boolean	false	Set to `true` to immediately run the check when the widget loads. Requires `data-domain`. Pair with `data-tool` to land the visitor on a complete result without any clicks.
`data-width`	CSS size	100%	Container width. Accepts any CSS length, percentage, or `auto`.
`data-max-width`	CSS size	700px	Caps the maximum rendered width. Set to a higher value for wide layouts, or shrink for sidebar embeds.
`data-max-height`	px integer	unset	When set, caps the iframe height to this many pixels and shows an internal scrollbar instead of growing to fit. Useful for sidebars, modals, and fixed-height dashboard tiles. Omit for natural auto-expand behavior.

Where it fits

Deliverability content, dashboards, audits, transparency pages

Anywhere a live reputation grade adds context for the reader.

ESP and CRM dashboards

Surface a live reputation grade alongside open and click rates so users diagnose deliverability without leaving the product.

Agency and consultant sites

Let prospects audit their own domain on your homepage and use the result as the opening line of the discovery call.

Email tool comparison pages

Add interactive proof to deliverability content. Readers grade a domain inline instead of bouncing to a separate tool.

Status and transparency pages

Show your own domain's reputation publicly. A simple trust signal that costs nothing to add.

FAQ

Common questions about the widget

If you don't see your question, email support@senderreputation.org.

Yes. The widget is free to embed on any website, including commercial sites. There is no signup, no API key, no payment, and no expiry. Usage is subject to a fair-use per-IP rate limit that mirrors the limits applied to our own tools.

Nine: the Sender Reputation Checker, SPF, DKIM, DMARC, Blacklist, MX, and Reverse DNS checkers, plus searchable Bounce Code and Glossary references. You can embed every tool (visitors switch from a dropdown), a subset (e.g. just SPF and DKIM), or a single tool with the menu pinned. Use data-tools="reputation,spf,dkim" or data-tools="glossary" on the script tag.

Yes. Drop the script tag in multiple places - each instance renders independently with its own iframe. You can even pin each one to a different tool, e.g. one widget showing the SPF checker and another showing the bounce code lookup.

No. As of widget version 2.0, the widget works on any domain with no whitelist required. Paste the script and it loads immediately.

The script tag injects a lightweight iframe that loads our checker UI from senderreputation.org. The iframe communicates its rendered height back to the parent page via postMessage so the embed grows and shrinks naturally as users open accordion sections.

No. The embed loader is a small async script that defers iframe rendering until after your page paints. It blocks nothing in the critical path, and the iframe itself is lazy-loaded by the browser.

Yes. The widget supports three themes: Light, Dark, and Auto. Auto follows the visitor's operating system preference using prefers-color-scheme. You can also constrain the width with data-width and data-max-width attributes.

Yes. Each visitor's IP is allowed a fair number of checks per hour, the same limit applied to our public tools. The 429 response is forwarded back to the user in the widget UI when reached. Results are cached for one hour so repeat lookups on the same domain return instantly.

No cookies are set by the widget. The iframe issues a single request to our public reputation API when a visitor submits a domain. No personally identifying information is collected or stored beyond a short-lived IP-based rate counter.

The Sender Reputation Checker runs the full analysis - SPF, DKIM, and DMARC authentication, DNS-based blacklist status across the major providers, MX and PTR records, mail server infrastructure, and overall DNS configuration - and presents it as an A-F grade. The individual tools (SPF, DKIM, DMARC, Blacklist, MX, Reverse DNS) drill into one specific piece of that puzzle and return a focused verdict plus the underlying record. The Bounce Code and Glossary tools are searchable references that index the same 50+ SMTP codes and 70+ deliverability terms used on the main site.

By default the widget is 100% of its container with a maximum width of 700 pixels. Override either value with the data-width or data-max-width attributes on the script tag.

The small Powered by link is part of the free terms. It keeps the widget free and helps cover the cost of running the API, so please leave it in place.

Anywhere you can paste raw HTML. That includes WordPress (use a Custom HTML block or a code widget), Webflow Embed elements, Wix HTML iframe widgets, Squarespace Code blocks, Ghost HTML cards, plain static sites, React or Next.js pages (drop the tag inside dangerouslySetInnerHTML or a Script component), Shopify Liquid templates, and any framework that accepts HTML.

The current widget version is 2.0. The src URL is unversioned so installed embeds always receive the latest patch automatically.

One tag away.

Copy the snippet, paste it into your page, you're live. No signup, on any domain.

index.html

Widget v2.0 · auto-sizing iframe · no signup required