Calculator bot

Where most calculator bots in this category require you to open a private chat, mathcalcbot works inline: type @mathcalcbot, a space, and an expression in the text field of any chat, and Telegram shows a preview of the computed answer that you can tap to send. That single detail makes it noticeably faster to use in the middle of a group conversation than a bot you'd otherwise have to switch away to.

It supports the standard four operators and parentheses, plus two functions — sin and sqrt — which covers a step above pure arithmetic without turning into a full scientific calculator. Its own listing gives 2+2, 4(5/3) and sin(60)sqrt(16)/.3 as example queries, and it links out to a written manual on Telegra.ph with more samples, which is unusually thorough documentation for a bot this small.

The function set is the main limitation: no cosine, tangent, logarithms or exponents beyond what you can spell out manually, and no visible monthly-user count to judge how widely it is actually used. If you only need sin and sqrt alongside basic arithmetic and want the convenience of inline mode, it is a solid pick; for anything more mathematically demanding, look at calcubot or Wolfram Alpha instead.