# Type systems with matching sans, serif and mono families > Families designed to be used together: a sans, a serif or slab and often a monospace that share proportions, weights and character. The hardest part of pairing typefaces is that two good fonts can still disagree. Their x-heights differ, so text in one looks a size larger than the other. Their bolds are not equally bold. One is warm and the other mechanical. A type system avoids the problem at the source: its sans, serif and monospaced members are designed to a shared plan, with heights, weights and spacing tuned to sit together. That makes these families a safe route to a multi-voice layout. A common arrangement is the sans for interface and headings, the serif for long reading, and the monospace for code, data or captions. Another is the reverse, with serif headlines over sans body text. Either way you can switch family in the middle of a line, for a term in code or a quotation in serif, and the line keeps its rhythm. Systems vary in size. Some have just two members, a sans and its monospace or a serif and its sans; others add a slab, a display cut or further widths. The members below are grouped by system, and each note names the siblings that are in this catalog. If you already use one family from a system, its partner is the first pairing to try. How these were chosen: Families that belong to a named type system with at least two members in this catalog, as sans, serif, slab or monospaced member; members are listed next to their siblings. ## Fonts (26) - [Roboto](https://trendhub.net/fonts/roboto.markdown) (Sans Serif, 18 styles · variable, OFL): The sans of a system that also has slab, serif and fixed-width members in this catalog. - [Roboto Slab](https://trendhub.net/fonts/roboto-slab.markdown) (Slab Serif, 9 styles · variable, Apache 2.0): The slab serif of the Roboto family, a companion to the sans on the same skeleton, in nine upright weights. - [Roboto Serif](https://trendhub.net/fonts/roboto-serif.markdown) (Serif, 18 styles · variable, OFL): The reading serif under the Roboto name, matching the sans with nine weights and italics. - [Roboto Mono](https://trendhub.net/fonts/roboto-mono.markdown) (Monospace, 14 styles · variable, OFL): The monospaced member of the Roboto family, its shapes adapted to one width, in seven weights with italics. - [IBM Plex Sans](https://trendhub.net/fonts/ibm-plex-sans.markdown) (Sans Serif, 14 styles · variable, OFL): The sans of a corporate family with sibling Serif and Mono designs in the same seven weights. - [IBM Plex Serif](https://trendhub.net/fonts/ibm-plex-serif.markdown) (Serif, 14 styles, OFL): The serif of the Plex family, built as the reading companion to its sans and mono, in seven weights with italics. - [IBM Plex Mono](https://trendhub.net/fonts/ibm-plex-mono.markdown) (Monospace, 14 styles, OFL): The monospaced member of IBM Plex, in the same seven weights with italics as the sans and serif. - [Source Sans 3](https://trendhub.net/fonts/source-sans-3.markdown) (Sans Serif, 16 styles · variable, OFL): An interface sans with a transitional serif partner and a fixed-width coding companion in the Source family. - [Source Serif 4](https://trendhub.net/fonts/source-serif-4.markdown) (Serif, 16 styles · variable, OFL): A transitional serif made to accompany Source Sans, matching its proportions and the gray value of its text. - [Source Code Pro](https://trendhub.net/fonts/source-code-pro.markdown) (Monospace, 16 styles · variable, OFL): The monospaced companion adapted from Source Sans, keeping its vertical proportions and general shapes. - [Noto Sans](https://trendhub.net/fonts/noto-sans.markdown) (Sans Serif, 18 styles · variable, OFL): The core sans of the Noto collection, with a serif and a fixed-width sans as its partners. - [Noto Serif](https://trendhub.net/fonts/noto-serif.markdown) (Serif, 18 styles · variable, OFL): The serif of the Noto collection, the partner of Noto Sans: nine weights with italics. - [Noto Sans Mono](https://trendhub.net/fonts/noto-sans-mono.markdown) (Monospace, 9 styles · variable, OFL): The monospaced sans of the Noto collection, with the same nine weights and narrowing width axis as Noto Sans. - [PT Sans](https://trendhub.net/fonts/pt-sans.markdown) (Sans Serif, 4 styles, OFL): The first family of a public type project, joined by a matched serif and a fixed-width face, in Regular and Bold with italics. - [PT Serif](https://trendhub.net/fonts/pt-serif.markdown) (Serif, 4 styles, OFL): Harmonized with PT Sans in metrics, proportions and weights so the two can be combined, covering Latin and Cyrillic. - [PT Mono](https://trendhub.net/fonts/pt-mono.markdown) (Monospace, 1 style, OFL): The monospaced member of the PT family, sharing its design language with PT Sans and PT Serif, in Regular only. - [Fira Sans](https://trendhub.net/fonts/fira-sans.markdown) (Sans Serif, 18 styles, OFL): The sans of the Fira family, which also has a fixed-width variant, Fira Mono. - [Fira Mono](https://trendhub.net/fonts/fira-mono.markdown) (Monospace, 3 styles, OFL): The monospaced variant delivered alongside the Fira sans, in Regular, Medium and Bold. - [Merriweather](https://trendhub.net/fonts/merriweather.markdown) (Serif, 14 styles · variable, OFL): A screen text serif whose sans sister family was drawn to match it. - [Merriweather Sans](https://trendhub.net/fonts/merriweather-sans.markdown) (Sans Serif, 12 styles · variable, OFL): The low-contrast, semi-condensed sans built to harmonize with the serif Merriweather family. - [Space Grotesk](https://trendhub.net/fonts/space-grotesk.markdown) (Sans Serif, 5 styles · variable, OFL): A proportional sans derived from Space Mono, keeping the quirks of its fixed-width source. - [Space Mono](https://trendhub.net/fonts/space-mono.markdown) (Monospace, 4 styles, OFL): The fixed-width source of Space Grotesk: a display-minded monospace in Regular and Bold with italics. - [Red Hat Text](https://trendhub.net/fonts/red-hat-text.markdown) (Sans Serif, 10 styles · variable, OFL): The text cut of a family that also has a display cut and a fixed-width member, Red Hat Mono. - [Red Hat Mono](https://trendhub.net/fonts/red-hat-mono.markdown) (Monospace, 10 styles · variable, OFL): The monospaced member of the Red Hat type family, beside two proportional optical sizes, with italics. - [Geist](https://trendhub.net/fonts/geist.markdown) (Sans Serif, 18 styles · variable, OFL): The proportional half of the Geist project, with Geist Mono as its fixed-width companion in the same nine weights. - [Geist Mono](https://trendhub.net/fonts/geist-mono.markdown) (Monospace, 18 styles · variable, OFL): The monospaced half of the Geist project, matching the proportional sans in nine weights with italics. ## FAQs ### Why pair fonts from the same family system? They share proportions, x-height and weight steps, so text can change style without changing apparent size or color. That consistency is hard to get from unrelated typefaces. ### Which member should set headings and which the body? Either order works. Sans headings with a serif body feel bookish and calm; serif headings over sans text feel editorial. Use the monospace for code, figures and small labels. ### Is it boring to use only one type system? Not if you use its range: different weights, sizes, widths and the contrast between sans and serif give plenty of variety while keeping the page coherent. ### Can I use these families together in a commercial product? Yes. Nearly all are under the SIL Open Font License and Roboto Slab is under the Apache License 2.0; both permit commercial use, embedding and modification. Each font page states its license. ## Related collections - [Font families with nine weights and italics](https://trendhub.net/fonts/for/font-families-with-nine-weights.markdown) - [Serif fonts for long reading on screens](https://trendhub.net/fonts/for/serif-fonts-for-long-reading.markdown) - [Monospace fonts for coding](https://trendhub.net/fonts/for/monospace-fonts-for-coding.markdown) - [Humanist sans-serif fonts for readable text](https://trendhub.net/fonts/for/humanist-sans-serif-fonts.markdown) - [Slab serif fonts](https://trendhub.net/fonts/for/slab-serif-fonts.markdown) - [Clean sans-serif fonts for app interfaces](https://trendhub.net/fonts/for/app-interface-fonts.markdown) --- Source: https://trendhub.net/fonts/for/matching-sans-serif-and-mono-families (trendhub)