Khan Academy vs Grammarly: Which Is Better for Teachers?
Khan Academy is a free, nonprofit learning platform that teaches and practices entire subjects — math, science, reading, history, and official SAT prep — through videos, exercises, and mastery tracking; Grammarly is a writing assistant that checks grammar, clarity, tone, and originality on whatever a student is already writing. They rarely compete for the same task. One builds subject knowledge from the ground up; the other polishes the writing a student produces somewhere else.
Quick Answer: Choose Khan Academy when you need a full course of instruction and practice — math fluency, science concepts, reading comprehension, SAT readiness — tracked over an entire school year. Choose Grammarly when students are already writing and you want sentence-level feedback on grammar, clarity, and originality before you grade it. Most classrooms that use writing at all benefit from both, just for different halves of the work.
What Khan Academy and Grammarly Are Actually Built For
Khan Academy delivers instructional content and practice across whole subjects; Grammarly reviews and improves text a student has already written. That's the entire distinction in one sentence, but it shapes everything else — pricing, grade-level fit, privacy exposure, and how each tool sits inside a class period.
Khan Academy was founded in 2008 by Sal Khan as a 501(c)(3) nonprofit, built on the idea that anyone, anywhere, should have access to a free world-class education. It has since grown into a full mastery-learning platform: short instructional videos, unlimited practice exercises, progress dashboards, and — through a partnership with the College Board — official, free SAT practice tied directly to a student's actual PSAT results.
- Founded: 2008, San Francisco, by Sal Khan
- Structure: 501(c)(3) nonprofit, donor-funded
- Reach: Pre-K through early college, plus test prep
Grammarly launched in 2009 as a browser-based grammar checker and has expanded into a full writing assistant available as a browser extension, desktop app, and integration inside Google Docs and Microsoft Word. It doesn't teach a subject. It sits inside whatever a student is already writing — an essay, a lab report, a short-answer response — and flags grammar, punctuation, clarity, tone, and originality issues in real time.
- Khan Academy teaches the subject from the ground up.
- Grammarly reviews and improves whatever a student has already written.
- Neither one substitutes for the other — they sit at opposite ends of the same assignment.
| Dimension | Khan Academy | Grammarly |
|---|---|---|
| Core function | Full-subject instruction and mastery practice | Writing feedback layered onto existing text |
| Subject coverage | Math, science, humanities, ELA, test prep | Any subject involving written work |
| Primary output | Course progress, mastery scores, video lessons completed | Corrected, clarified, more original writing |
| AI tutoring | Khanmigo — Socratic-questioning AI tutor | AI-assisted rewrite and tone suggestions |
| Grade range | Pre-K through early college (Khan Academy Kids for ages 2-8) | Any grade level old enough to write independently |
| Cost model | Entirely free, nonprofit-funded | Free tier plus paid Premium and Business/Education tiers |
| Classroom role | Replaces or supplements direct instruction and homework practice | Sits alongside an existing writing assignment |
For where both fit into the broader landscape of teacher AI tools, see AI Education Tools Compared: The 2026 Buyer's Guide.
Where Khan Academy Excels
Khan Academy's strength is depth: a genuinely complete, free curriculum with mastery tracking, not a single tool bolted onto one assignment. For a teacher building an entire unit or year of instruction, that completeness is hard to match.
Full-course practice with mastery tracking
Khan Academy organizes content into courses — Algebra 1, Grade 5 math, AP Biology, US History — each broken into units with videos, guided practice, and mastery checks. A student's progress accumulates into a mastery score per skill, not just a completion checkmark, so a teacher can see exactly which sub-skill within fractions or photosynthesis still needs work.
- Assignable practice sets teachers can push directly to a class or an individual student.
- Real-time dashboards showing time spent, accuracy, and mastery level per skill.
- Self-paced remediation, letting a struggling student revisit a prerequisite skill without holding back the rest of the class.
Khanmigo: an AI tutor layered onto real curriculum content
Khanmigo is Khan Academy's AI tutoring assistant, built to ask guiding questions rather than hand a student the answer. Adoption grew sharply in the 2024-25 school year — Khan Academy's own annual report counted roughly 2 million students, educators, and parents using Khanmigo worldwide, a 731% year-over-year jump (Khan Academy, SY24-25 Annual Report).
That growth comes with a caveat worth knowing before you lean on it: Khan Academy has also reported that only about 15% of students with Khanmigo access use it regularly, despite more than 108 million tutoring interactions logged since its 2023 rollout (Khan Academy, SY24-25 Annual Report). Access isn't the same as habitual use — plan to actively introduce Khanmigo rather than assuming students will find it on their own.
Free, official SAT preparation
Khan Academy's SAT prep is built in partnership with the College Board and links directly to a student's PSAT/NMSQT results, generating a personalized practice plan from actual missed question types. For a teacher supporting juniors and seniors through standardized testing, that's a genuinely free alternative to paid test-prep services.
Where Khan Academy falls short: it has no dedicated grammar or style checker. A student can write a full essay response inside a Khan Academy exercise, but the platform won't flag a comma splice or a vague thesis statement the way a purpose-built writing tool does.
Where Grammarly Excels
Grammarly's strength is precision on the sentence and paragraph level — catching what a busy teacher reading 30 essays might miss on a first pass. It doesn't teach a subject; it improves the writing a student produces for any subject.
Sentence-level feedback on any assignment
Grammarly checks grammar, spelling, punctuation, clarity, conciseness, and tone in real time, wherever a student is typing — a Google Doc, a Word file, or directly in Grammarly's own editor. Because it isn't tied to a specific curriculum, it works identically whether a student is writing a history essay, a lab report, or a persuasive letter.
- Grammar and mechanics checks catch errors a spell-checker alone misses, like subject-verb agreement or misplaced modifiers.
- Tone detection flags when a formal assignment reads as overly casual, or vice versa.
- Clarity suggestions highlight run-on sentences and vague phrasing, prompting a student to revise before submission.
Built into the tools students already write in
Grammarly integrates directly with Google Docs, Microsoft Word, and most major browsers, so students don't need to switch to a separate app to get feedback. More than 40 million people use Grammarly daily as of 2025, and it's deployed at over 3,000 educational institutions (Grammarly, 2025). That kind of ambient integration matters for adoption — a tool students have to open separately gets used far less than one already sitting inside their draft.
Originality and writing-process checks for academic integrity
Grammarly's plagiarism and originality checks compare a submission against a large database of published and web content, and its Authorship feature can show a writing-process timeline — how much of a document was typed, pasted, or AI-generated — which is increasingly relevant as more student writing passes through generative AI tools somewhere in the process.
- Originality reports flag unattributed matches to existing text.
- Writing-process insight gives a teacher more signal than a static plagiarism score alone.
- Real-time use means students see flags while drafting, not just after submission.
Where Grammarly falls short: it has no instructional content of its own. It can't teach a student what a run-on sentence is conceptually or walk them through solving a quadratic equation — it only reacts to text already on the page.
How the two tools handle AI-assisted writing differently
Khan Academy's Khanmigo is designed to ask questions rather than write for a student; Grammarly's generative features can draft or rewrite text outright, which is a meaningfully different risk profile for academic integrity. A teacher setting expectations for either tool needs to be explicit about which mode is allowed for a given assignment.
- Khanmigo's tutor mode is built around Socratic prompting — it's designed to guide a student toward an answer, not generate a finished response for them.
- Grammarly's generative rewrite features can produce full replacement sentences or paragraphs on request, which is closer to co-writing than tutoring.
- Neither distinction is automatic — a student can still misuse either tool, so classroom norms matter more than the tool's default design.
According to Common Sense Media's ongoing reviews of education technology, transparency about how a tool uses AI — and what data it retains — is one of the clearest predictors of whether a school trusts a platform enough to scale it beyond a single classroom (Common Sense Media, 2024).
Head-to-Head on Specific Classroom Tasks
Set against an actual week of teaching, these two tools almost never compete for the same job.
| Task | Better fit | Why |
|---|---|---|
| Building a full year of math practice with mastery tracking | Khan Academy | Purpose-built courses with per-skill mastery scoring |
| Catching grammar and clarity issues in a student essay | Grammarly | Real-time, sentence-level writing feedback |
| Preparing juniors for the SAT | Khan Academy | Free, official College Board partnership |
| Checking a submission for unattributed or AI-generated text | Grammarly | Originality checks and Authorship writing-process view |
| Assigning self-paced remediation on a specific math skill | Khan Academy | Mastery dashboards pinpoint the exact weak skill |
| Improving tone and formality in a persuasive essay draft | Grammarly | Tone detection built into the live editor |
| Teaching a science concept through video and guided practice | Khan Academy | Full video library paired with practice exercises |
| Polishing a lab report before it's submitted | Grammarly | Works inside Google Docs where the report is already written |
Privacy, Compliance, and Cost
Both tools carry real privacy considerations, just tied to different kinds of student data — practice performance for Khan Academy, and the actual content of student writing for Grammarly.
What each platform collects
Khan Academy, used heavily by children under 13 through Khan Academy Kids and elementary courses, publishes a COPPA-aligned privacy policy and does not run third-party advertising on student accounts. Grammarly for Education processes the literal text of student writing to generate suggestions, which means district agreements should specifically address how that text is stored and whether it's used to improve Grammarly's underlying models.
- Ask whether your district's data agreement already covers Khan Academy's practice and progress data.
- Confirm whether Grammarly for Education's institutional terms differ from the free consumer tier most students might already be using at home.
- Route the decision through your school's technology office rather than treating either as a low-stakes individual-teacher choice.
CoSN's annual survey of K-12 technology leaders has consistently ranked student-data privacy among the field's top concerns (CoSN, 2024). For a fuller vetting framework specific to generative AI tools, see Is ChatGPT FERPA Compliant? What Schools Need to Know.
Cost and access
| Plan | Khan Academy | Grammarly |
|---|---|---|
| Free tier | Entirely free — full course library and Khanmigo access reported at no cost to individual educators | Yes — core grammar and spelling checks |
| Paid tier | None; nonprofit, donor-funded | Premium (individual) plus Business and Education institutional licenses |
| Typical buyer | Individual teacher, school, or district at no direct cost | Individual teacher, department, or district license |
| Notable backing | Funded by donors including major philanthropic foundations | Privately held; reported 2025 annual revenue exceeding $700 million (Grammarly, 2025) |
For teachers weighing free options more broadly before adding a paid writing tool, see The Best Free Alternative to TeachMate AI.
Using Both in the Same Classroom
Because Khan Academy and Grammarly sit at opposite ends of the instructional process, running both isn't redundant — it's two different checkpoints in the same unit.
Say you teach Grade 7 ELA and you're wrapping up a persuasive-essay unit tied to a current-events topic. A student could use Khan Academy's reading and writing courses to build background skills earlier in the unit, then draft the actual essay in Google Docs with Grammarly running in the background to catch grammar issues and flag an overly casual tone before you ever see the draft. That pairing frees your grading time for the parts of the essay Grammarly can't judge — argument quality, evidence selection, and structure.
- Use Khan Academy earlier in a unit to build foundational skills or reteach a prerequisite concept.
- Bring in Grammarly once students start drafting, so mechanical issues surface before submission rather than during grading.
- Keep your own feedback focused on argument, structure, and content — the layer neither tool fully covers.
- Use EduGenius to generate the actual assignment materials — a differentiated writing prompt, a rubric, or a comprehension quiz tied to the reading — pulling the unit together from instruction through assessment.
For a workflow-building comparison in the same pillar, see Eduaide.ai vs Pear Deck: Which Is Better for Teachers? and Eduaide.ai vs NotebookLM: Which Is Better for Teachers?.
Grade-Level Fit
Khan Academy scales cleanly from early childhood through early college; Grammarly becomes useful the moment a student is writing independently enough for grammar feedback to matter.
- Grades K-2: Khan Academy Kids offers early literacy and math activities appropriate for this age. Grammarly isn't a fit yet — most students this age aren't writing independently in a format Grammarly can meaningfully review.
- Grades 3-6: Khan Academy's core courses cover the bulk of daily math and reading practice. Grammarly becomes relevant as students start writing multi-paragraph responses, though teacher oversight of its suggestions still matters at this age.
- Grades 7-9 and beyond: Both tools see their heaviest use here — Khan Academy for expanding subject coverage and, eventually, SAT prep, and Grammarly for the growing volume of essays, reports, and long-form writing middle and high school require.
Pro Tips for Getting the Most from Either Tool
A handful of habits separate classrooms that get consistent value from these tools from those that try them once and drift away.
- Assign specific Khan Academy skill practice tied to what you just taught, rather than open-ended "go practice math" time — mastery tracking works best against a specific target.
- Introduce Khanmigo deliberately, since Khan Academy's own data shows most students with access don't use it without a nudge.
- Set Grammarly's goals (audience, formality, domain) per assignment so its tone suggestions match what you're actually grading for.
- Review Grammarly's Authorship report on a flagged submission before assuming misconduct — it shows a process timeline, not a verdict.
What to Avoid
Most disappointment with either tool comes from expecting it to do the other one's job.
- Expecting Grammarly to teach a concept. It reacts to text already written; it has no lesson content, videos, or guided practice.
- Expecting Khan Academy to catch grammar and style issues in a written response. Its practice exercises aren't built as a writing-feedback tool the way Grammarly is.
- Letting either tool's suggestions substitute for your own review of argument and content, especially on high-stakes writing.
- Assuming free consumer-tier Grammarly and a school's Grammarly for Education license have identical data terms — check before treating them as interchangeable.
Key Takeaways
- Khan Academy and Grammarly solve different problems: full-subject instruction and mastery practice versus sentence-level writing feedback.
- Khan Academy is entirely free, nonprofit-funded, and spans Pre-K through early college, including an official College Board SAT-prep partnership.
- Khanmigo adoption grew sharply in SY24-25 — roughly 2 million users, up 731% year-over-year — though only about 15% of students with access use it regularly (Khan Academy, 2025).
- Grammarly reaches more than 40 million daily active users and is deployed at 3,000+ educational institutions as of 2025 (Grammarly, 2025), working inside Google Docs and Word rather than as a standalone destination.
- Neither tool replaces the other — Khan Academy builds subject knowledge; Grammarly polishes writing a student produces elsewhere.
- Privacy review should be specific to each tool's data type: practice performance for Khan Academy, actual written text for Grammarly.
- Most writing-heavy classrooms benefit from pairing both, using each at a different point in the same assignment.
Frequently Asked Questions
Is Khan Academy or Grammarly better for teachers?
It depends on the task. Khan Academy is better for teaching and practicing an entire subject — math, science, reading, or SAT prep — with mastery tracking over time. Grammarly is better for catching grammar, clarity, and originality issues in writing students have already produced. Most classrooms with any writing component benefit from using both at different points in a unit.
Can Grammarly replace Khan Academy's instructional content?
No. Grammarly has no lessons, videos, or guided practice — it only reviews and suggests changes to text already written. A student who doesn't understand a grammar rule conceptually won't learn it from Grammarly's inline suggestions alone; Khan Academy's instructional videos are built for that kind of foundational teaching.
Does Khan Academy check for plagiarism or AI-generated writing?
Not directly. Khan Academy's practice exercises focus on skill mastery, not writing-integrity checks. If academic integrity in written work is the concern, Grammarly's originality checker and Authorship writing-process feature are purpose-built for that job.
Are both tools free for classroom use?
Khan Academy is entirely free, funded as a nonprofit. Grammarly offers a free tier with core grammar and spelling checks, with Premium and institutional Education licenses available for advanced features like tone detection, originality checks, and the Authorship report.
Related Reading
- AI Education Tools Compared: The 2026 Buyer's Guide
- The Best Free Alternative to TeachMate AI
- Eduaide.ai vs NotebookLM: Which Is Better for Teachers?
- Claude vs Khan Academy: Which Is Better for Teachers?
- Eduaide.ai vs Pear Deck: Which Is Better for Teachers?
- Is ChatGPT FERPA Compliant? What Schools Need to Know