Quick calculators for everyday finance.
Use these on the fly - no signup, no email capture. Built by our team for the questions clients ask us most.
When to use it
Working out the VAT element of a supplier invoice, pricing a new product gross-of-VAT, or sense-checking a customer quote. Defaults to the UK standard rate of 20%, with reduced (5%) and zero options.
A note on accuracy
Results are rounded to two decimal places using standard arithmetic. For VAT returns, always reconcile against your accounting software and HMRC submissions.
When to use it
Modelling savings growth, comparing loan offers, or projecting the cost of a director's loan. Pick the compounding frequency that matches the underlying product.
Want a fuller forecast?
Our advisory clients get a full 13-week cash forecast modelled on real bank data. Ask us about the Growth or CFO Partner package.
Self-Assessment Estimator for Sole Traders
Use this free UK self assessment calculator to get an instant income-tax estimate as a sole trader. Enter your self-employed income, allowable expenses, and a few personal details to see a clear breakdown of your estimated tax bill and how much to set aside each month. Updated for the 2024/25 and 2025/26 tax years.
When to use this tool
This self employed income tax estimator is designed for UK sole traders who want a quick, clear picture of their likely tax bill before filing their Self Assessment return. Use it to:
- Plan quarterly tax savings so you are never caught short at the January deadline.
- Model the impact of additional income - a new contract, rental income, or side project.
- Check whether your bookkeeping for sole traders captures all allowable expenses.
- Prepare for an accountant conversation with realistic numbers.
Accuracy disclaimer
This tool provides an estimate only and does not constitute tax advice. Figures are based on published HMRC rates for the selected tax year and may not reflect your individual circumstances. Always confirm your final liability with a qualified accountant before submitting your Self Assessment return.
Ready for tax-ready accounts?
AccoTiva's bookkeeping service keeps your records clean, your expenses captured, and your Self Assessment straightforward - all year round, not just in January.
Frequently asked questions
How is the income tax calculated?
The estimator deducts allowable business expenses from gross self-employed income to find taxable profit. It adds any other taxable income, subtracts your Personal Allowance, then applies UK income tax bands: 20% Basic Rate (up to £37,700 above the Personal Allowance), 40% Higher Rate (£37,701 to £125,140), and 45% Additional Rate above that.
What is the Personal Allowance for 2025/26?
The standard Personal Allowance for 2025/26 (and 2024/25) is £12,570. It tapers by £1 for every £2 above £100,000 total income, disappearing entirely above £125,140. Adjust the override field if yours differs.
How does National Insurance work for sole traders?
Sole traders pay Class 4 NI on profits above £12,570: 6% up to £50,270, then 2%. Class 2 NI at £3.45/week applies once profits exceed the Small Profits Threshold of £12,570.
What counts as an allowable business expense?
HMRC allows deductions for costs that are wholly and exclusively for business use: materials, professional subscriptions, software, business travel, marketing, and a proportion of home-working costs. Good bookkeeping for sole traders ensures you capture every eligible expense.
Sales Tax by ZIP Code — US Online Sellers
Use this free US sales tax lookup to quickly find the estimated combined state and local sales tax rate by ZIP code. Enter your sale amount to see the estimated tax due and total price. Built for D2C brands, Shopify sellers, and e-commerce businesses navigating US sales tax compliance.
Enter a ZIP code and state, then click Look up sales tax rate to see the estimated combined rate.
Who this tool is for
This sales tax calculator for online sellers is designed for:
- D2C brands selling physical goods direct to US consumers via their own store
- Shopify and WooCommerce sellers checking whether they have sales tax nexus in a new state
- E-commerce businesses pricing products and estimating checkout totals for US buyers
- UK and international sellers expanding into the US market and new to e-commerce sales tax USA rules
- Bookkeepers and accountants reviewing client sales records for compliance
Nexus & marketplace facilitator rules
US sales tax is governed by individual states, not federal law. Key concepts to know:
- Economic nexus: Most states require you to collect sales tax once you exceed a threshold (usually $100,000 in sales or 200 transactions in a year in that state), even if you have no physical presence there.
- Marketplace facilitators: If you sell through Amazon, Etsy, or eBay, the platform typically collects and remits sales tax on your behalf in most states. You may still need to track separately.
- Origin vs. destination sourcing: Most states use destination-based sourcing (tax is based on where the buyer is), but a few use origin-based sourcing.
- Product exemptions: Groceries, clothing, and digital goods have varying exemption rules by state.
Need help with sales tax bookkeeping?
US sales tax compliance is complex, especially for growing e-commerce and D2C brands. AccoTiva helps online sellers keep clean records, track nexus thresholds, and stay audit-ready — whether you sell on Shopify, Amazon, or your own store.
Markup vs Margin Calculator — COGS & Profit
Use this free margin calculator to instantly find your gross profit, profit margin %, and markup % from your cost of goods sold and selling price. Add optional shipping, platform fees, and a desired margin target to model your pricing with confidence. Built for e-commerce sellers, retailers, restaurants, and service businesses.
Enter your cost and selling price, then click Calculate margin & markup to see your profit breakdown.
When to use this calculator
This markup vs margin calculator is useful whenever you need to:
- Price a new product — work backwards from your target margin to find the right selling price
- Check your e-commerce margins — factor in Shopify, Amazon, or Etsy fees to see your true take-home profit
- Calculate restaurant food cost margins — use COGS to confirm your menu pricing covers labour and overheads
- Compare wholesale vs retail pricing — understand how markup and margin differ at each stage
- Model platform fee impact — see instantly how a 3–15% marketplace fee affects your bottom line
Why margin matters
Margin and markup are often confused — but they measure very different things:
- Profit margin is profit as a percentage of revenue. A 40% margin means you keep $0.40 of every $1.00 sold after covering COGS.
- Markup is profit as a percentage of cost. A 67% markup on a $12 product gives a $20 selling price — but only a 40% margin.
- Break-even price is the minimum you must charge to recover all costs. Selling below this means a loss on every unit.
- Target margin pricing lets you work backwards from the profit you need, not just guess a number that “feels right.”
Want cleaner numbers behind your margins?
AccoTiva helps e-commerce brands, retailers, and restaurant operators keep their COGS accurate, their overheads tracked, and their pricing profitable — all year round, not just at year-end.