Free calculators and tools for paid ads, tracking, social media and selling online, with a guide to the numbers that decide whether marketing pays.
Good marketing decisions come down to a few numbers: what a customer costs to win, what they’re worth, and whether each channel pays for itself. This guide covers the tools for paid ads, tracking, social media and selling online, in the order most businesses need them. Everything runs in your browser, and nothing you enter is stored.
Pick the right tool
| I want to… | Use this |
|---|---|
| Know the ROAS I need to make a profit | Break-Even ROAS Calculator |
| Check whether my ads are profitable | ROAS Calculator · Marketing ROI |
| Plan a monthly ad budget | Ad Budget Planner · Facebook Ad Cost |
| Work out CPC, CPM, CPA or CTR | CPC, CPM & CPA · CTR |
| Know what a customer is worth | Customer Lifetime Value · CAC |
| Tag links so I can see results in GA4 | UTM Campaign URL Builder |
| Find out if an A/B test result is real | A/B Test Significance · Sample Size |
| Check Google or Meta ad text fits | Google Ads Headline Checker · Meta Ads Text Preview |
| See my profit after marketplace fees | Amazon FBA · Etsy · eBay · Shopify |
| Measure social media engagement | Instagram · TikTok |
1. Start with the numbers that decide profit
Before you spend on ads, work out how much you can afford to pay for a sale. Two numbers do most of the work.
- Break-even ROAS. Return on ad spend is revenue divided by ad spend. To break even, ROAS has to be at least 1 divided by your gross margin. With a 40% margin, that’s 1 ÷ 0.40 = 2.5, so every £1 of ads must bring in £2.50 of sales just to break even. The break-even ROAS calculator works this out, along with the most you can pay per sale (CPA).
- Customer lifetime value (LTV) and acquisition cost (CAC). If customers buy again, a first sale at a loss can still pay off. Many businesses aim for LTV at least three times CAC. Use the lifetime value calculator and the CAC calculator together.
A high ROAS can still lose money if your margin is thin or returns are high. If ROAS looks good but the bank balance doesn’t, read why ROAS can look good while a business loses money.
2. Plan and run paid ads
Work backwards from your goal. If you want 50 sales a month, your site converts 2% of visitors and clicks cost £0.80, you need 2,500 clicks and about £2,000 of spend. The ad budget planner does this sum for you. Then check the ads themselves before they go live.
Google Ads
- Responsive search ads allow up to 15 headlines of 30 characters and up to 4 descriptions of 90 characters: headline checker.
- Build and tidy keyword lists: keyword combiner, match type converter and negative keyword list builder.
- Find what’s dragging down your Quality Score: Quality Score explainer.
- Check a Performance Max asset group: Performance Max asset checker.
Meta (Facebook and Instagram)
- Preview your text and see what gets cut off: Meta ads text preview.
- Estimate reach, clicks and sales from a budget: Facebook ad cost calculator.
- Get pixel event code for purchases and leads: Meta Pixel event code generator.
- Review a struggling account step by step: how to audit a Facebook ads account.
3. Track results properly
If you can’t measure it, you can’t improve it. Add UTM tags to every link you share in emails, social posts and ads, so Google Analytics 4 shows which campaign each visit came from. Use the UTM campaign URL builder and keep the same lower-case naming every time, because GA4 treats “Facebook” and “facebook” as different sources.
- Install tags: Google Tag Manager snippet.
- Name custom events correctly: GA4 event name validator.
- Find where people leave your funnel: funnel drop-off calculator and conversion rate calculator.
Test before you trust
A small difference between two versions of a page or ad is often just chance. Decide how many visitors you need before you start with the A/B test sample size calculator, let the test run for at least a full week, and only then check the result with the A/B test significance calculator.
4. Social media
Engagement rate is a fairer measure than follower count, because it shows how many people actually react. Track it over time with the Instagram and TikTok engagement rate calculators.
- Plan a month of posts: social media content calendar.
- Get sizes and limits right: image size guide, LinkedIn character counter and X character counter.
- Price sponsored content or estimate creator income: influencer rate calculator and YouTube money calculator.
- Let customers message you in one tap: WhatsApp link generator.
5. Selling online
Platform and payment fees add up quickly, so work out your profit per order after every fee before you set a price.
| Where you sell | Tool |
|---|---|
| Amazon | Amazon FBA calculator |
| Etsy, eBay and Depop | Etsy · eBay · Depop |
| Your own shop | Shopify profit · Dropshipping profit |
| Card and PayPal payments | Stripe fees · PayPal fees |
| Setting prices | Product pricing · Markup · Average order value |
Running a UK online shop also means publishing some policies. Customers buying online can usually cancel within 14 days of delivery without giving a reason, and you must tell them how. You also need a privacy notice explaining how you use their data. Start with the return policy, privacy policy and terms and conditions generators, then have them checked for your business. For stock, use the SKU generator and barcode generator.
6. Review everything regularly
Once a quarter, step back and check the whole picture with the 24-point marketing audit checklist, then compare each channel’s return with the marketing ROI calculator.
All marketing and ads tools
E-Commerce
- Amazon FBA CalculatorProfit per unit after Amazon referral, fulfillment and storage fees.
- Average Order Value CalculatorAOV, conversion rate and the revenue gain from bigger baskets.
- Barcode GeneratorCode 128, EAN-13 and UPC barcodes as PNG or SVG.
- Depop Fee CalculatorDepop fees and payout for UK and US sellers.
- Dropshipping Profit CalculatorProfit per order after product, shipping, fees, ads, refunds and VAT, plus break-even ROAS.
- eBay Fee CalculatoreBay US and UK selling fees and profit after fees.
- Etsy Fee CalculatorEtsy fees and profit per sale for US and UK shops.
- Markup CalculatorSelling price from cost and markup, with margin and profit.
- PayPal Fee CalculatorPayPal fees in the US and UK, what you receive and what to charge.
- Privacy Policy GeneratorPlain-English privacy policy for UK GDPR, EU GDPR and more.
- Product Pricing CalculatorSelling price from cost with a target margin or markup, plus VAT.
- Return Policy GeneratorCreate a returns and refunds policy for a UK online shop, based on consumer law.
- Shopify Profit CalculatorProfit per order and per month after Shopify fees, costs and ads.
- SKU GeneratorCreate consistent SKU codes for products and variants, and copy them as CSV.
- Stripe Fee CalculatorSee Stripe fees for UK and US accounts, and what to charge to receive a set amount.
- Terms and Conditions GeneratorWebsite and online shop terms with UK consumer rights.
Paid Ads & Analytics
- A/B Test Sample Size CalculatorHow many visitors your A/B test needs, and how long to run it.
- A/B Test Significance CalculatorCheck whether the difference between two conversion rates is statistically significant.
- Ad Budget PlannerWork out the monthly ad budget you need from your goal, conversion rate and cost per click.
- Break-Even ROAS CalculatorFind the ROAS and CPA you need to break even or hit a target margin.
- Conversion Rate CalculatorConversion rate with a confidence range, revenue per visitor and targets.
- CPC, CPM & CPA CalculatorCost per click, per thousand impressions and per conversion, plus CTR and conversion rate.
- CTR CalculatorClick-through rate, CPC and CPM from impressions, clicks and spend.
- Customer Acquisition Cost CalculatorCompare customer acquisition cost by channel, with blended CAC and LTV:CAC.
- Customer Lifetime Value CalculatorWork out customer lifetime value, LTV:CAC ratio and CAC payback.
- Facebook Ad Cost CalculatorEstimate impressions, clicks, sales and cost per result from your Meta ads budget.
- Funnel Drop-Off CalculatorStep-by-step funnel conversion and the stage where most people leave.
- GA4 Event Name ValidatorCheck GA4 event and parameter names against Google’s rules and reserved names.
- Google Ads Headline CheckerCheck responsive search ad headlines and descriptions against Google limits.
- Google Ads Quality Score ExplainerSee what to fix first from your expected CTR, ad relevance and landing page ratings.
- Google Tag Manager Snippet GeneratorGet the Google Tag Manager install code for your container ID.
- Keyword CombinerCombine keyword lists into every combination, with match types.
- Keyword Match Type ConverterConvert keywords to broad, phrase or exact match, or negatives.
- Marketing Audit ChecklistA 24-point marketing checklist with a score and the area to fix first.
- Marketing ROI CalculatorROI and ROAS for each marketing channel, after your gross margin.
- Meta Ads Text PreviewPreview a Facebook or Instagram feed ad and check primary text, headline and description lengths.
- Meta Pixel Event Code GeneratorMeta Pixel base code and standard event snippets like Purchase and Lead.
- Negative Keyword List BuilderBuild negative keyword lists from common themes and your search terms.
- Performance Max Asset CheckerCheck a Performance Max asset group against Google’s requirements.
- ROAS CalculatorWork out ROAS, profit after ad spend, break-even ROAS and the ROAS you need for a profit target.
- UTM Campaign URL BuilderBuild tagged campaign URLs for Google Analytics 4 with source, medium, campaign, term and content.
Social Media
- Emoji PickerSearch and copy emoji for posts, captions and messages.
- Facebook Post PreviewPreview how a post, link card and image may look in the feed.
- Fancy Text GeneratorInstagram fonts to copy and paste: bold, script, gothic and more.
- Influencer Rate CalculatorA fair starting price for sponsored posts, Reels, TikToks and videos.
- Instagram Engagement Rate CalculatorEngagement rate by followers and reach from your recent posts.
- LinkedIn Post Character CounterCount characters against LinkedIn's 3,000 limit and see what shows before See more.
- LinkedIn Text FormatterBold, italic and bullets for LinkedIn posts, with a preview.
- Social Media Content CalendarPlan posts by date and platform, then download as CSV or print.
- Social Media Image Size GuideRecommended image sizes for Instagram, Facebook, X, LinkedIn, YouTube, TikTok and Pinterest.
- TikTok Engagement Rate CalculatorEngagement rate by views and followers for TikTok videos.
- WhatsApp Link GeneratorCreate a wa.me click-to-chat link with a message and QR code.
- X (Twitter) Character CounterCount characters the way X does, with links at 23 and emoji at 2.
- YouTube Money CalculatorEstimate YouTube earnings from views and RPM, for long-form and Shorts.
- YouTube Thumbnail DownloaderGet any YouTube video's thumbnail in HD, standard, high and medium sizes.
Related guides
- Finance calculators: profit margins, VAT, invoices and pricing.
- Job search and CV tools: CVs and interview help for marketing roles.
- SEO tools: titles, schema, sitemaps and technical fixes.
Results depend on the figures you enter. Platform fees and ad limits change, so each tool shows when it was last checked. Confirm current fees with the platform before you set prices.
Frequently asked questions
What is a good ROAS?
It depends on your margin. You break even when ROAS equals 1 divided by your gross margin, so 2.5 at a 40% margin or 4 at a 25% margin. Anything above that is profit before other costs.
What is the difference between ROAS and ROI?
ROAS compares revenue with ad spend only. ROI compares profit with the total cost, so it accounts for product costs, fees and other spending.
What are UTM parameters?
Tags added to the end of a link, such as utm_source and utm_campaign, that tell Google Analytics where a visit came from.
How long should an A/B test run?
Until it reaches the sample size you planned, and for at least one full week so every day of the week is included. Stopping early because one version looks ahead often gives false results.
Are these tools free?
Yes. Every tool is free, needs no account and runs in your browser, so your figures aren’t sent anywhere.
Sources
- Google Ads Help: About responsive search ads
- Google Analytics Help: Collect campaign data with custom URLs
- GOV.UK: Online and distance selling for businesses
- ICO: The right to be informed (privacy notices)
- Consumer Contracts Regulations 2013
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