Commas, colons and capitalisation

Apple

Best for: technology terminology.

Updated every year and free to read on the web or as a PDF, the Apple Style Guide is really a dictionary of terms with strong opinions attached. It’s at its best on technology words, capitalisation and, increasingly, inclusive language, and it’s endearingly strict: it would rather you recast a whole sentence than let it begin with a capitalised “IPhone”. Less help if you want guidance on sentences rather than words, but if you write about software or hardware it settles a lot of arguments.

Visit the Apple Style Guide

Atlassian

Best for: product and interface writing.

Tucked inside Atlassian’s larger design system, the content section is a tidy lesson in how to write for a product. The voice is summed up in four words – bold, optimistic, practical, “with a wink” – and the guidance underneath covers everything from button text to error messages, with examples throughout. It isn’t a general reference, and you have to go digging past the colour palettes and components to find it, but as a worked example of codifying voice and tone for software it’s one of the better ones.

Visit the Atlassian content guidelines

BBC

Best for: editorial standards and judgement.

Not a style guide in the comma-and-colon sense at all – and that’s exactly why it earns its place. The BBC’s Editorial Guidelines set out how the corporation actually decides things: due accuracy, impartiality, fairness, and chapters with titles like “Harm and Offence” that most organisations never get round to writing down. If the guide you need is one that governs judgement rather than spelling, few organisations show their workings this openly, or at this scale. Refreshed in 2025, and more gripping than a book of rules has any right to be.

Visit the BBC Editorial Guidelines

Canada Post

Best for: UX writing and readability.

A lovely design system, well kept and plainly still in daily use. Mercury’s writing guidance is the draw: it aims for roughly an eighth-grade reading level, keeps lines to 60–70 characters, insists on plain-language error messages over codes, and does the whole thing bilingually. It’s built for Canada Post’s own products, but the principles travel further than the parcels do.

Visit the Canada Post Mercury guidelines

Conscious Style Guide

Best for: inclusive, conscious language.

Language doesn’t just describe the world; it can shape it, perpetuating discriminatory beliefs and behaviour. The Conscious Style Guide, founded and tended by Karen Yin, is the best place we know to start. Rather than pretend to hold every answer, it gathers articles, guides and resources on writing about people with care, grouped by subjects such as disability, age, ethnicity, gender and more, and points outward generously.

Alongside it, the Diversity Style Guide pulls more than 700 terms into a single searchable reference, and Hanna Thomas’s A Progressive’s Style Guide (written in 2016 but still very relevant) remains a brave, balanced take on the hardest questions around gender, ethnicity and violence, with patient explanations of why one form may be kinder than another.

Visit the Conscious Style Guide

Google

Best for: technical documentation.

Free, thorough and refreshingly willing to commit, Google’s developer documentation style guide is exactly what it says it is: a guide for writing technical docs. It’s clear on the things documentation teams squabble over – the serial comma, second person, present tense, active voice – and its word list bans “simply” and “easy” on the sensible grounds that nothing is, for everyone. If you’re not writing documentation a fair bit won’t apply, but for those who are, it’s a solid default.

Visit the Google style guide

Gov.uk

Best for: plain, no-nonsense public-sector writing.

With an authority that’s hard to argue with, the government’s own style guide is accessible and straightforward, and especially pertinent to policy teams. It’s not the most comprehensive – entries are usually extremely brief – but it has the courage of its convictions: it cheerfully bans “leverage”, “robust” and “deliver”, on the grounds that pizzas and post are delivered, abstract concepts are not.

Visit the Gov.uk style guide

The Guardian

Best for: UK editorial and not-for-profits.

The Guardian’s editorial guide is wide and deep, well researched, and the one that we use. It covers language that’s particularly useful for not-for-profit organisations.

It isn’t kept up to date quite as keenly as it once was, and its A-to-Z is weirdly sorted chronologically on its landing page, making it awkward to navigate, but occasional glimpses of a bitingly sharp sense of humour (we still miss David Marsh) more than make up for it.

Visit the Guardian style guide

Intuit

Best for: digital and product teams.

If Mailchimp’s guide whetted your appetite, this is the bigger meal. Intuit folded sixteen separate internal guides – Mailchimp’s, TurboTax’s, QuickBooks’ and more – into one public content-design system, and the join barely shows: clear principles, generous examples, and sections running from the basics of good content through to the fine grain of product and interface writing. It’s the most complete modern guide on this list.

Visit Intuit Content Design

Louder Than Ten

Best for: tone, voice and writing well.

This one is more about how to write well than a reference guide to grammar and spelling. But it nails tone and voice so brilliantly that it deserves a place in any style guide round-up. Packed full of advice-jewels such as “Don’t waste time milling around your topic with long intros or slow anecdotes. Strike swift and to the heart. Write like you could die of tuberculosis tomorrow.”

Visit the Louder Than Ten manual

Mailchimp

Best for: a ready-made starting template.

Mailchimp’s style guide has a website of its own and is well designed and easy to use. There are good sections on tone and structure as well as a shorter word list. It’s excellent for editorial advice, slightly less useful for checking spelling variations. It’s published under a Creative Commons licence, so it could make a good basis for your own tailored version.

Visit the Mailchimp style guide

Microsoft

Best for: everyday digital writing.

Quietly excellent. The Microsoft Writing Style Guide replaced the old Manual of Style and reads as though it was built for the web rather than a print bindery: warm, plain, accessibility-minded, with a strong word list and a sensible set of top ten tips. It will happily tell you to use contractions and to start a sentence with “And” if it reads better. It’s free, searchable and kept current, and for the everyday business of writing on screen it’s the one we’d point most teams to first.

Visit the Microsoft Writing Style Guide

Monzo

Best for: tone of voice.

More inspiration than reference, Monzo’s tone-of-voice page is a small masterclass in sounding human without sounding daft. It rests on three principles – straightforward kindness, everyday magic and warm wit – and, tellingly, it knows when to put the wit away: none of it in customer service, where the cost of a misjudged joke outweighs the pleasure of a good one. It won’t help you with a hyphen; it will help you find a personality.

Visit the Monzo tone of voice

NHS

Best for: plain language and accessibility.

If you read only one guide on this list, this is a strong candidate. The NHS digital service manual’s content guide is plain language done with real rigour – written for a reading age of around nine, accessibility-first, and unsentimental about clarity, because for the NHS a misread instruction can be a matter of safety rather than style. Even if you never write a word about health, it will make your writing clearer and kinder.

Visit the NHS content guide

Worth buying

The web has set most good style guides free, but a few of the best still live between covers, or behind a login. These are the ones that earn the outlay.

The Chicago Manual of Style

Best for: the definitive ruling.

The closest thing the English-speaking world has to a referee. Now in its 18th edition (2024), Chicago is exhaustive, unashamedly American, and the book a great many publishers reach for first. The full text is online by subscription – with a 30-day free trial, should you only need to win one almighty argument and then cancel.

Visit the Chicago Manual of Style

The Economist Style Guide

Best for: opinionated, quotable usage.

The Economist’s online guide has sadly gone, but the book endures, and it remains a pleasure. It still opens by quoting Orwell’s seminal Politics and the English Language before reaching for Mark Twain and Fowler, and the advice that follows is as acerbic and quotable as that pedigree promises. Thinner than the Guardian’s, but a good deal more fun to read.

Visit The Economist Style Guide

New Oxford Style Manual

Best for: the British desk reference.

For British editors, this is the one that earns its place on the desk. It binds New Hart’s Rules together with the Oxford Dictionary for Writers and Editors, so you get both the how – punctuation, hyphenation, capitalisation – and the which, in 25,000 entries on spellings and confusables. Less lively than the others here, but unmatched when you need a definitive British answer and you need it now.

Visit the New Oxford Style Manual

Also worth knowing: the AP Stylebook, the standard in American journalism (online by subscription), and Fowler’s Modern English Usage, the enduring classic for questions of idiom and good usage.