一目了然

• Pinyin: yī mù liǎo rán
• Hanzi breakdown: 一 = one (single); 目 = pictographic eye; 了 = 子 without one stroke (a child fully developed — to finish/complete, here meaning 'thoroughly'); 然 = 月 + 犬 + 火 (flesh + dog + fire — meat roasting on fire, used as 'so/thus' marker)

Meaning

Clear at a glance; immediately obvious; self-evident. Describes information or a situation that is so clearly presented that its meaning is understood instantly without explanation.

A four-character idiom (成语) used to praise clarity of presentation — whether in data visualisation, writing, design, or logical argument. Often applied to charts, labels, summaries, and structured reports. Contrasted with complicated or opaque information.

Examples

1. 报告附上了一张详细的折线图，将过去五年各季度的销售数据以视觉化方式呈现，让读者一目了然。 The report included a detailed line chart that visualized the sales data for each quarter over the past five years, making it clear at a glance.
2. 优秀的用户界面设计应做到功能分区合理、标识清晰，使初次使用的用户也能一目了然地找到所需操作入口。 Great user interface design should have sensible functional sections and clear labels, so even first-time users can immediately see where to go for what they need.
3. 这位侦探将所有嫌疑人的作案时间轴并排列在白板上，不同颜色的标记让案情的矛盾之处一目了然。 The detective laid out the timelines of all the suspects side by side on the whiteboard, and the different colored markers made the contradictions in the case obvious at a glance.

Usage Guide

Context: data, design, writing, analysis

Tone: positive

Do Say

• 新版财务报表采用了色彩编码与图形化呈现相结合的设计方案，各项成本构成和利润分布一目了然，大大降低了非财务背景管理人员的阅读门槛。(The new version of the financial statement adopts a design combining colour coding with graphical presentation; the composition of various costs and profit distribution are immediately obvious at a glance, greatly lowering the reading threshold for management personnel without a financial background.)
• 工程师将整个系统的数据流向用流程图加以梳理，各模块之间的依赖关系与数据传输路径一目了然，为后续的架构优化工作提供了清晰的参照依据。(The engineer organised the data flow of the entire system using a flowchart; the dependency relationships between modules and the data transmission paths are clear at a glance, providing a clear reference for subsequent architecture optimisation work.)

Don't Say

• 这件事还不够一目了然 — while grammatically possible, 一目了然 is binary in practice (either it is or it isn't); saying 还不够一目了然 is redundant if you mean 'not yet clear'; simply say 还不够清晰 or 还不够直观

Origin & History

一目 (a single glance — 目 = eye) + 了然 (to become thoroughly clear — 了 = fully/completely, 然 = so/thus) — literally 'one glance and it is thoroughly clear'

Cultural Context

Era: Classical/Modern

Generation: All ages

Social background: Universal