Ludwig is an AI-powered English writing assistant that helps you find example sentences, check grammar, and improve your writing using reliable sources from reputable publications.

Is Ludwig free to use?

Ludwig offers both free and premium plans. The free plan provides basic access to our features, while the premium plan unlocks advanced tools, unlimited searches, and additional writing assistance features.

How does Ludwig help with English learning?

Ludwig provides contextual example sentences from reliable sources like The New York Times, BBC, and academic publications, helping you understand how words and phrases are used in real-world contexts. This improves both writing fluency and comprehension skills.

Ludwig is trusted by students, teachers, researchers, and professionals worldwide. It's used by top universities including MIT, Stanford, Harvard, and Oxford, as well as professionals in tech companies like Adobe.

What makes Ludwig different from other writing tools?

Ludwig focuses on providing real example sentences from authoritative sources, not just grammar checking. This contextual approach helps users understand not just what's correct, but how language is actually used by native speakers and professional writers.

Used and loved by millions

Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak

CEO of Professional Science Editing for Scientists @ prosciediting.com

Please enter only digits
Grammar usage guide and real-world examples

USAGE SUMMARY

"please enter only digits" is correct and usable in written English
You could use it as part of an instruction in a document such as a form, as in "Please enter your phone number. Please enter only digits, not letters or special characters."

✓ Grammatically correct

Forms

Data Entry

Instructions

Table of contents

Usage summary

Human-verified examples

Expert writing tips

Linguistic context

Ludwig's wrap-up

Alternative expressions

FAQs

Human-verified similar examples from authoritative sources

Similar Expressions

60 human-written examples

Please enter only once.

News & Media

Huffington Post

Phone is required, and please enter numbers Only.

Academia

Harvard University

Please enter a 10-digit US mobile number.

News & Media

The New York Times

Note: When prompted, please enter your 8-10 digit Student ID number to receive credit for completion.

Academia

University of California, Berkeley

It read, as snippily as text can sound, "Please enter your 10-digit evening contact telephone number that you provided when ordering your Internet service, or your Login Code.

News & Media

The New York Times - Tech

Please enter the last seven digits of your NHS number into your HealthSentry device sponsored by Nivea Visage, and read out the resultant 16-letter Medicode.

News & Media

The Guardian - Opinion

Please enter a valid age.

News & Media

The Washington Post

Please enter your information to continue.

News & Media

The New York Times

Please enter a year from 1917 to 2017.

News & Media

The Washington Post

For now, please enter your questions.

News & Media

The New Yorker

Please enter on 79th Street and Columbus Ave.

News & Media

The New York Times

Expert writing Tips

✓ Best practice

When designing forms, use input masking to automatically format the user's input as digits, improving the user experience and reducing errors.

⚠ Common error

Failing to validate input can lead to errors. Always implement server-side validation to ensure that only digits are processed, even if client-side validation is in place.

Antonio Rotolo, PhD

Digital Humanist | Computational Linguist | CEO @Ludwig.guru

Linguistic Context

The phrase "please enter only digits" functions as an imperative instruction, directing the user to provide a specific type of input. As stated by Ludwig AI, this type of instruction can be commonly found in forms.

Expression frequency: Rare

✓ Frequent in

News & Media

30%

Academia

25%

Wiki

20%

⚠ Less common in

Science

10%

Formal & Business

10%

Reference

Ludwig's WRAP-UP

The phrase "please enter only digits" serves as an imperative instruction, primarily used to guide users on the specific format of input required, as Ludwig AI indicates. While grammatically sound and widely understandable, the phrase appears infrequently. The register is neutral, fitting diverse contexts from user interfaces to technical documents. Usage analysis reveals its prevalence in news, academia, and wiki sources. When constructing forms or input fields, ensure input validation is implemented to ensure accurate data collection, providing helpful error messages to guide users. Alternative phrases like "enter numbers only" or "digits only" offer similar instructions with slight variations in formality and emphasis.

Alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

Enter numbers only

Omits the politeness marker "please" for brevity.

Use digits only

Simple and direct instruction, dropping "enter".

Digits only

Shortest and most direct instruction, suitable for interfaces.

Enter numeric values

A more general alternative, specifying values as numeric.

Numerical values only

More formal and explicit, useful in technical documentation.

Please type digits only

Replaces "enter" with "type", more specific to keyboard input.

FAQs

How do I tell someone to enter only numbers?

You can use phrases like "enter numbers only", "digits only", or "numerical values only".

What is the best way to validate that a user has entered only digits?

Implement both client-side and server-side validation. Client-side validation provides immediate feedback, while server-side validation ensures data integrity.

Is it better to say "enter digits only" or "enter only digits"?

"Enter only digits" is generally preferred for clarity, but both are understandable. The placement of "only" emphasizes that digits are the sole acceptable input.

What should I do if a user enters non-digit characters?

Provide clear error messages indicating that only digits are allowed and guide the user on how to correct their input.

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Table of contents

Usage summary

Human-verified examples

Expert writing tips

Linguistic context

Ludwig's wrap-up

Alternative expressions

FAQs

Source & Trust

83%

Authority and reliability

4.5/5

Expert rating

Real-world application tested

Most frequent sentences:

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Please enter only digitsGrammar usage guide and real-world examples

Please enter only digits
Grammar usage guide and real-world examples