Contribute to the world's largest email benchmark dataset

Help Build More Accurate Email Benchmarks

Forward .eml files or upload exported emails to contribute real campaign data. All PII is stripped. In return, get higher-resolution benchmarks for your industry.

Or simply forward .eml files to contribute@competitorinbox.com

More Accurate Benchmarks

Every .eml file you contribute adds real-world sending data that improves industry-level benchmarks for everyone.

Premium Industry Segments

Contributors get early access to niche sub-industry segments and higher-resolution benchmark breakdowns.

Fully Anonymised

We strip all personally identifiable data before analysis. No subscriber names, no contact lists — only aggregate send metrics.

How It Works

01

Export emails from your ESP

In most ESPs (Mailchimp, Klaviyo, Iterable, Salesforce Marketing Cloud, etc.), go to a sent campaign and choose "Export" or "Download" — selecting .eml format.

02

Drop files here or use your email app

Drag-and-drop .eml files into the form below, or forward raw emails to contribute@competitorinbox.com — we accept individual .eml files and .mbox archives.

03

We anonymise, extract metrics and attribute

Our pipeline strips PII, extracts send-time, subject length, template structure, and campaign-level stats (if embedded in headers), then rolls them into benchmark segments.

How to export .eml files from popular email clients

Gmail

Open the email → ⋮ More menu → Download message. Saves as .eml.

Outlook (desktop)

Drag-and-drop an email from the list onto your desktop. Saves as .msg (we'll handle that) or .eml.

Apple Mail

File → Save As → Format: Raw Message Source (.eml).

ESP Campaign Export

Most ESP platforms (Mailchimp, Klaviyo, etc.) have a "Preview source" or "Export HTML" option per campaign.

Upload .eml Files

Drag & drop .eml or .mbox files here

or click to browse · max 25 MB per file

Personally identifiable data (To, From addresses, subscriber names) is removed from all files before processing. We only retain aggregate campaign metrics. See our Privacy Policy.

Common Questions

Q: What data is actually extracted?

Send date/time, subject line length and word count, template section count, email client rendering hints from headers, and any campaign-level stats Klaviyo/Mailchimp embed in X-headers. No subscriber-level data.

Q: Will my subscribers' emails appear anywhere?

No. The To/From/Reply-To fields and all X-Original-To headers are the first thing we strip. Only the broadcast metadata goes into our pipeline.

Q: Can I contribute competitor emails?

Yes — if you're subscribed to a competitor's list and have received their campaign emails to your own inbox, forwarding those is 100% fine. Same data goes in; it's the publicly broadcast campaign.

Q: What do contributors get back?

Contributors who supply their email address get early access to updated benchmark reports, sub-industry splits (e.g., D2C vs Amazon-native for retail), and higher granularity confidence scores.

Want to benchmark your competitors directly?

Competitor Inbox captures every email campaign your competitors send — not just aggregated stats.

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