Free tools

Useful things, no signup.

Calculators and generators for the problems email operators actually hit. Every one runs entirely in your browser — nothing is uploaded, nothing is stored, and none of them ask for your address.

Markup calculator →Browse the glossary
2 tools available
Cost

What email actually costs you.

FREE

Per-email markup calculator

Work out what your current platform charges you for delivery you could buy directly.

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Deliverability

Deliverability tools

FREE

DMARC record generator

Build a valid DMARC record, with every tag explained in plain English.

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On the way

Being built next.

Listed here rather than kept in a private roadmap. If one of these would be useful sooner, tell us and it moves up.

  • SPF, DKIM & DMARC checkerCheck a domain’s authentication records and flag misalignment.
  • IP & domain warmup plannerGenerate a day-by-day sending ramp for a new domain or IP.
  • Deliverability scorecardScore your bounce, complaint and delivery rates against real thresholds.
  • Email footer compliance checkerCheck an email for the identity, address and unsubscribe elements the law requires.
  • Lawful basis wizardWork out which lawful basis applies and what evidence you need to keep.
  • Gmail clipping checkerFind out whether Gmail will clip your email, and what is making it heavy.

Tools are free.
So is Sandbox.
Try the product.

Brands, consent records, providers, and workflows in test mode — before you pay anything.

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