Great Presentation = Happier Customers

As new devices and applications are constantly introduced, it's increasingly difficult to ensure consistent design and user experience across your campaigns.

Ensure Quality

You've spent countless hours assembling your creative. 250ok Design helps you ensure that it's presented to your customers in the way you envisioned. Effective, optimized communication means highly engaged recipients.

Fix Broken Images & Links

Large file sizes, broken images or links, and invalid markup are just a few issues we'll help you fix. 250ok's optimization engine provides actionable feedback and suggestions on how to optimize your campaign for success.

Test Common Spam Filters

250ok Design tests your creative against common spam filters including Barracuda, Symantec, Spam Assassin, Outlook, and many more so you can identify and fix spam triggers before deploying your campaign.

250ok works with any email service provider

MailChimp Salesforce Act-On Marketo Adobe SendGrid Maropost SparkPost

How email previewing works:


Test any campaign or template

You can easily create a test by importing templates from your email service provider or by uploading your campaign's HTML.


We'll capture the screenshots

Using the industry's leading rendering providers – Litmus and Email on Acid - we'll capture email previews in more than 70 clients and devices.


Review the results

Identify issues before you send by combining your email previews and spam filter results alongside 250ok's world-class deliverability tools.

Resources for #SeriousSenders

Seedlist-based inbox monitoring 250ok Return Path eDataSource

Seedlist-Based Inbox Monitoring the Right Way

When sending commercial email, it’s important to understand what’s likely to happen the next time you send to a recipient at a particular mailbox provider. Are your messages hitting SPAM at Yahoo! or going missing at Comcast? Are you sacrificing ROI because you lack the proper visibility into performance? Seedlist-based inbox monitoring is a key […]

IP and Domain Warming, a Medieval Perspective

Marketers are often confused about the point of IP and domain warming, and they end up wondering: “Everything is authenticated, and I’m not using a blacklisted IP, so what’s the problem?” In short: senders who blast to their entire list without history look like spammers. Internet service providers (ISPs) can choose what to accept or […]

The Truth About Email Panel Data

We’re often asked about our stance on the use of email panel data. As senders, we want additional data points, visibility, and signals. In a perfect world, email panel data would enable marketers to compare their engagement to that of their competitors within a contextually relevant group of subscribers. Collected ethically and without bias, this […]

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