Formal Informal Word Swapper
Swap casual wording for formal equivalents and back again using 112 register pairs, with risky swaps kept optional.
About this tool
Formal Informal Word Swapper
Swap casual wording for formal equivalents and back again using 112 register pairs, with risky swaps kept optional.
Formal Informal Word Swapper rewrites a block of text between registers using 112 paired equivalents — phrasal verbs, everyday vocabulary, connectives, contractions, hedges and email openings. Eighty of the pairs are marked safe, meaning the swap holds in essentially any sentence; the other thirty-two depend on the sentence and are applied only if you ask for them, because 'about' should not become 'regarding' in 'about ten kilos'. Longer phrases are replaced before shorter ones and your original capitalisation is preserved, so 'Can't' becomes 'Cannot' rather than 'cannot'.
How to use Formal Informal Word Swapper
- 1
Open Formal Informal Word Swapper on AltFTool — it loads instantly in your browser.
- 2
Paste an email, a paragraph or a whole draft into Your text.
- 3
Set Direction to 'Informal → formal' or 'Formal → informal', optionally use 'Limit to a category' for phrasal verbs, contractions, hedges or email openings, and tick the context-dependent swaps to include them.
- 4
Read Swaps applied and the Converted text with every replacement listed by category and warning, then press Copy text.
Why use Formal Informal Word Swapper
Risky swaps are opt-in
Context-dependent pairs are separated from the safe ones and only applied when you switch them on.
Both directions
Formal to informal is included, which is useful for cutting bureaucratic padding out of a draft.
Every change is listed
You see each replacement with its category and any warning attached, rather than a silently rewritten block.
Common use cases
- Turn a quick draft into something you can send to a client, replacing phrasal verbs and contractions in one pass.
- Soften an over-stiff paragraph by running it the other way — utilise back to use, commence back to start.
- Show an English class exactly which words carry register, by converting only the phrasal-verb category.
- Check a cover letter for casual openings such as 'Hi' and sign-offs such as 'Cheers' before you send it.
Frequently asked questions
What makes writing formal or informal in English?
Register shows up mostly in four places: phrasal verbs (find out versus determine), contractions (can't versus cannot), hedges and intensifiers (a bit, really, kind of), and greetings. Sentence length and passive constructions matter too, but swapping those four categories moves a text further than anything else.
Should I avoid contractions in formal writing?
In academic papers, contracts and official letters, yes — write cannot, do not, it is. In business email and most web copy, contractions now read as natural rather than sloppy, so the rule is about the document type, not about English generally.
Is 'utilise' more formal than 'use'?
It is longer, not better. Style guides consistently advise against 'utilise' where 'use' works, because it adds syllables without adding meaning. This tool includes the pair but marks it as context-dependent with that warning attached.
Will this rewrite my sentences?
No. It substitutes words and fixed phrases only. Real formality also comes from sentence structure and from what you choose to say, so read the output before sending it — a word-level swap cannot fix a sentence that is rude or unclear to begin with.