GrammarBot

Free plan API

What GrammarBot is

GrammarBot Neural is a REST API for developers adding grammar and spelling correction to applications or services. It checks grammar, spelling, and punctuation, then returns corrected submitted text. An optional apply=xml parameter adds markup identifying edits. English is the documented default language, and GrammarBot asks users to contact it about another language. The API is hosted on RapidAPI and requires an API key. Requests should contain plain text; the documentation warns that HTML, tables, and irregular formatting may not produce satisfactory results. Each request can contain up to 5,000 characters, with a plan-based rate limit of 1–3 requests per second and a daily limit of 15,000 requests. GrammarBot says submissions are processed in real time and are not stored, retained, or logged, although request metadata may remain. SSL/TLS encrypts data in transit. A free plan includes 500 requests monthly. Paid Neural plans use monthly character volumes, while the Standard API uses character-based pricing, including a listed $0.02 per 1000 characters for lower volume.

Who it suits

GrammarBot suits developers integrating English grammar, spelling, and punctuation correction into software through an API. It is intended for applications and services that can send plain-text requests and handle API authentication.

What it does well

Checks grammar, spelling, and punctuation
Returns corrected text and optional edit markup
Free plan includes 500 requests monthly
Submissions are not stored or logged
SSL/TLS encrypts data in transit

What to know first

English is the documented default language
Requests are limited to 5,000 characters
RapidAPI hosting requires an API key
HTML and tables may produce unsatisfactory output

Plans

Plan	Billed and limits	Price
Free	500 requests per month	Free
Neural: less than 3 million characters	Characters submitted per month · Less than 3 million characters per month	$0.02 a month
Neural: 3 million to 12 million characters	Characters submitted per month · 3 million to 12 million characters per month	$0.02 a month
Neural: 12 million to 30 million characters	Characters submitted per month · 12 million to 30 million characters per month	$0.01 a month
Neural: more than 30 million characters	More than 30 million characters per month	On request
Standard API	$0.02 per 1000 characters for less than 3 million characters/month · Character-based pricing · 3–12 million: $0.015 per 1000 characters · 12–30 million: $0.01 per 1000 characters · over 30 million: contact us	$0.02 a month

As grammarbot.io lists them, read 21 Sept 2026. The maker's own page has the final word.

Verdict

GrammarBot offers a focused correction API with plain-text input, edit markup, and documented request limits. Developers should account for English-first language support, RapidAPI authentication, and character-based paid plans.

Facts from GrammarBot's own pages

API access: The Neural API is currently hosted on RapidAPI and requires an API key. · docs.grammarbot.io, 7 Oct 2026
Browser extension: No · docs.grammarbot.io, 21 Sept 2026
Company: The privacy policy identifies Oasic Technologies LLC and gives its address as 1107 Bayswater Drive, Union, KY 41091. · grammarbot.io, 7 Oct 2026
Correction markup: An optional `apply=xml` parameter returns markup specifying edits to the input text. · docs.grammarbot.io, 7 Oct 2026
Corrections: The API checks grammar, spelling, and punctuation and returns a corrected version of submitted text. · docs.grammarbot.io, 7 Oct 2026
Data providers: The privacy policy names Stripe for payment processing and Amazon Web Services and Vultr for hosting and IT infrastructure. · grammarbot.io, 7 Oct 2026
Desktop app: No · docs.grammarbot.io, 21 Sept 2026
Founded: The About page says the team recognized the need for an accurate, affordable grammar-checking API in 2018. · grammarbot.io, 7 Oct 2026
Free plan: Yes · docs.grammarbot.io, 21 Sept 2026
Input format: The API documentation says input should be plain text and warns that HTML, tables, and irregular formatting may not produce satisfactory output. · docs.grammarbot.io, 7 Oct 2026
Input limits: The documentation lists a maximum of 5,000 characters per request, a rate limit of 1–3 requests per second based on plan, and a 15,000-request daily limit. · docs.grammarbot.io, 7 Oct 2026
Intended users: The maker describes GrammarBot as an affordable grammar and spelling API for developers to integrate into applications and services. · grammarbot.io, 7 Oct 2026
Language: English is the documented default language, and the page says to contact GrammarBot to request another language. · docs.grammarbot.io, 7 Oct 2026
Languages supported: 1 · docs.grammarbot.io, 21 Sept 2026
Latency and uptime: The pricing page states that 90% of requests complete in under one second, 96% in under two seconds, and uptime is 99.99%. · docs.grammarbot.io, 7 Oct 2026
Mobile app: No · docs.grammarbot.io, 21 Sept 2026
Privacy: The privacy policy says API submissions are processed in real time and are not stored, retained, or logged, though request metadata may be retained. · grammarbot.io, 7 Oct 2026
Product: GrammarBot Neural is a deep learning-based REST API for grammar and spell checking. · docs.grammarbot.io, 7 Oct 2026
Style suggestions: No · docs.grammarbot.io, 21 Sept 2026
Support: The maker lists [email protected] for technical and other questions. · grammarbot.io, 7 Oct 2026
Tone detection: No · docs.grammarbot.io, 21 Sept 2026
Transmission security: The privacy policy says API data is encrypted in transit using SSL/TLS. · grammarbot.io, 7 Oct 2026

Where GrammarBot stands on Freedom251

Grammar checkers#64 of 88