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Email Campaign Toolbox

Nine rules-based tools built by an email specialist. Everything runs in your browser — no accounts, no servers, no data leaving your device.

Start with the Subject Line Tester ↓
Use the ↑ ↓ arrows to build your workflow — your order is saved automatically
✍️ Write it right
Tool 1 of 9
Read the guide →

Subject Line Tester

Write subject lines that actually get opened. Check length, spam risk, emoji rendering, and readability — and see a live inbox preview before you commit.

Mobile cut-off (~35 chars) 0 / 35
Outlook cut-off (~60 chars) 0 / 60
Gmail cut-off (~90 chars) 0 / 90
—
Score / 100
Enter a subject line to get your score.

Spam Trigger Words

Enter a subject line above.

Emoji Rendering Preview

—

Mini Inbox Snippet

Your Brand Now
Write a subject line above
Tool 2 of 9
Read the guide →

Preheader Optimiser

Your preheader is the most underused real estate in email. See exactly how your subject and preheader appear together across every major client — and get instant advice on how to improve them.

0
Subject chars
0
Preheader chars
0
Combined chars
—
Score / 100

How it looks in each client

💡 What makes a great preheader?

✅ Extends the subject — adds context, don't just repeat it
✅ 50–90 chars — enough to show on most clients
✅ Front-load the most important words — mobile cuts off quickly
✅ Include a soft CTA — "See what's inside →" works well
❌ Don't leave it blank — clients will pull random copy instead
❌ Don't repeat the subject line word for word
🔧 Build & check
Tool 3 of 9
How-to guide — coming soon

Email Read Time Optimiser

Find out if your email is actually easy to read. Paste your copy and get an instant read time, readability score, and plain-English advice on how to improve it.

0
Words
0s
Est. read time
0
Sentences
—
Flesch score
HardStandardEasy

Skimmability Analysis

Paste text above to analyse.
Tool 4 of 9
How-to guide — coming soon

Inbox Preview Simulator

Know exactly what lands in the inbox before you hit send. Preview your subject line and preheader across Gmail, Outlook, and mobile — no guessing.

0
Subject chars
0
Preview chars
0
Subject words
0
Preview words
Subject line length Enter a subject line
0 33 — universal safe zone 48 — iPhone Mail max 90

Per-client subject line preview

Tool 5 of 9
How-to guide — coming soon

UTM Builder — Email Focused

Turn any link into a trackable URL so you know exactly which emails drive traffic and conversions. Pre-filled with email marketing best practices.

Quick-fill templates

Your last URL is saved locally for next visit.

📐 GA4 naming rules — keep your data clean

✅ Always use lowercase — email not Email
✅ Use hyphens not spaces — summer-sale not summer sale
✅ Be consistent — pick one name and stick to it across all campaigns
✅ UTM values are case-sensitive in GA4 — mismatches split your data
Enter a URL to get started
Tool 6 of 9
How-to guide — coming soon

Plain Text Email Generator

Every HTML email should have a clean plain text version — it improves deliverability, looks professional in email clients that prefer it, and is required for spam compliance. Paste your HTML or copy below and get a clean, formatted plain text version instantly.

📬 Send strategy
Tool 7 of 9
How-to guide — coming soon

Send Time Optimiser

Stop guessing when to send. Get tailored send time recommendations based on your audience, industry, and email type — with the reasoning explained so you understand the why.

%

Account for seasonality

Adjusts recommendations for Q4 peaks, summer slowdowns, and holiday periods

Select your audience type and email details above — your tailored send time recommendations will appear here.
🗂️ Organise
Tool 8 of 9
Read the guide →

Campaign Naming Generator

Keep your campaigns organised and easy to track. Generate clean, consistent names across every channel — and pick up right where you left off.

— Fill in the fields above —

Format breakdown — drag chips to reorder

Fill fields to see breakdown

💡 Custom naming templates coming soon — get in touch if you’d like early access.

Tool 9 of 9
How-to guide — coming soon

Image & Asset Naming Convention

Generate clean, consistent, searchable filenames for every image in your library. Build one field at a time, or paste raw metadata and we'll extract only what matters.

Build your filename token by token. The output follows the pattern: Size-Subject-Organisation-Photographer

How it'll be used — define your own conventions

What's in the image — no spaces, use CamelCase or hyphens

Short abbreviation works best

Surname or initials — keeps it short

Format options

Separator
Case
— Fill in at least Size and Subject above —

FORMAT BREAKDOWN — drag chips to reorder

Fill fields to see breakdown

💡 Tip: Lead with the size/usage label so assets sort by type in any file system or DAM — then subject, then org and photographer for rights traceability.

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It's free, ad-free, and always will be. If it's saved you time, a small contribution helps keep it that way.

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No AI. No prompts. No accounts. Every tool on this page runs entirely in your browser using deterministic, rules-based logic. Your email copy, subject lines, and campaign data are never sent to a server. The only storage used is your own browser's localStorage — and you can clear it any time.