You detect typography differences between Figma and the browser by comparing computed values against what the design specifies: font size, weight, line height, and letter spacing. The challenge is that most of these differences are too subtle to catch by eye, which means a direct measurement is more reliable than a visual check. A font weight that is one step off, a line height slightly too tight, letter spacing barely perceptible — none of these look obviously wrong until you put a number next to them.
The eye adapts to what it sees. A heading rendered at weight 400 instead of 500 looks like a heading. A paragraph with 1.4 line height instead of 1.5 looks like a paragraph. Neither triggers an obvious "something is wrong" response unless you are specifically looking for a discrepancy and have a reference to compare against.
This is especially true for the developer who built the implementation. They have been staring at it for hours. Their brain knows what it is supposed to look like and fills in the gap between what the design says and what the browser shows.
The properties that cause the most drift are predictable:
Font weight is the most common offender. The difference between 400 and 500 is subtle at body sizes. At heading sizes it changes the visual hierarchy but still reads as "a heading." It gets accepted and shipped.
Line height affects how dense or airy text feels. Too tight makes body copy feel crowded. Too loose makes it feel disconnected. Neither is obviously broken. Just slightly off.
Letter spacing is almost invisible at normal reading distances. A value of 0 instead of 0.02em on a heading is not something a glance will catch.
Font size discrepancies are more visible but still easy to rationalise. A heading at 30px instead of 32px looks close enough without a direct comparison.
The standard approach is to open Figma and the browser side by side and look. This catches the obvious deviations: a heading that is dramatically the wrong size, a font family that is clearly different. It does not reliably catch the subtle ones.
Measuring helps. Inspecting the rendered element in browser DevTools and comparing the computed values against what Figma specifies will surface exact discrepancies. The problem is the time it takes. On a page with ten text styles across thirty components, checking each computed value manually is slow enough that most developers do not do it fully.
The other problem is that DevTools shows computed values, not design intent. A computed line-height of 24px on a 16px font is 1.5, but whether that matches the Figma specification requires looking it up in the design file. That back-and-forth between two tools, for every element, for every property, adds up quickly.
An automated comparison against the Figma design measures rendered typography values against design specifications geometrically. It does not rely on the eye to notice that something is off. It checks whether the font size is correct, whether the weight is right, whether line height and letter spacing reflect what the design says.
The output is a list of specific differences with values: "font weight is 400, design specifies 500." That is faster to act on than a vague impression that something looks slightly light. It also catches the deviations that would never surface in a manual check because it measures everything, not just what catches the eye. Letter spacing at 0 instead of 0.01em. Line height one unit off. These get found.
Typography drift most commonly enters during initial implementation, when values get approximated or pulled from the wrong token. Running a comparison before submitting for review catches it while the relevant code is still open and the fix is straightforward.
Re-running after a design system update is also worth doing. A token change that cascades through the codebase can shift typography values across pages without any individual component appearing broken.
Uiprobe compares rendered web pages against Figma designs and surfaces typography differences with specific values: font size, weight, line height, letter spacing, and more. Try it free.
Stop pixel-peeping by hand.
Free to start. No credit card. See your first comparison in under a minute.
The fastest way to see how your implementation compares to the design. No screenshots, no guessing
who is it for
Company
© 2026 · Built by UIPROBE
